Auto Prophet Defends Pushrods
We’re not sure exactly who The Auto Prophet is, but he points out the merits of the pushrod engine, including its advantages as a platform for advanced technology, compact design that is easy to package within a motor compartment and great power and torque curves:
The Redemption of the Pushrod? Various pundits occasionally slap GM for selling pushrod engines. I have even been known to do it myself. But I have come to understand and respect GM’s use of OHV designs, and the critics should stop and think about it for a few minutes.
We agree, and those are some of the reasons why we continue to develop OHV technology. We’d like to hear your reactions.
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I’m not a gearhead, but here’s my reaction. My late grandfather used to own a 1991 Buick LeSabre with the 3800 engine. I know you are still using essentially the same engine. At the time, I thought the car had plenty of pep. My ‘02 Acura 3.2 TL is probably a smaller engine, but the overall driving experience is much better. The car is more solid on the road and the acceleration is smoother.
I know, I’m comparing apples and oranges, but my point is still that if you can provide that kind of driving experience with OHV technology, then OHV’s are fine. If you can’t, then you should be working on how to give drivers an optimal experience. Also don’t know if OHV engines have anything to do with this or not, but certain Pontiacs and Buicks sound like lawn mowers.
Here is a numerical comparison of the LS7 (new pushrod Z06 engine) and the S65 (new mill in the BMW M5/M6 which won International Engine of the Year):
http://www.my350z.com/forum/showthread.php?t=124068
I find it mildly amusing that the linked article uses BMW’s system as an example of how complex variable displacement is in a OHC application.
Of course, the article conveniently ignores Honda’s rather simple and straight forward 3 valve VTEC system. Which, by odd coincidence, is the very engine GM is offering as an option in the Saturn Vue and Honda has recently introduced variable displacement on.
The article also conveniently skirts the fact that those BMW engines put out prodigious amounts of power for their displacement (ie HP/liter). Far more than the typical OHV engines of comparable displacement. So the complexity does yield a return.
It’s quite easy to find opinion pieces to support a particular point of view but my larger question is this: If GM is so confident that their current engine lineup and mix is, in fact, so competitive, why is this question even being asked?
GM’s problem isn’t OHC vs OHV. It’s that GM lets their engines (and a lot of other things) go way, way too long without complete re-engineering.
On the other hand, the longer an engine stays in production the longer time available to amortize the tooling for the line. A cost issue to be sure.
But gee whiz, isn’t a quarter century , or more, a bit much?
And why isn’t Ford offering variable displacement on any of their engines?
I don’t know, why not ask them? On the other hand why did GM back away from CVT when Ford, and a few other manufacturers, are embracing it?
Different perpectives result in different solutions. And that’s signficant how?
It only becomes signficiant if one path is empirically shown to be superior to the others taken.
I have owned GM cars with both ohv and ohc. As good as the northstar is, there is nothing like the instant torque of a small block. Its versatility is unmatched by any other engine unless it is another pushrod V8. With a auto it is great but with a 6 speed it is essential. Nothing but nothing beats torque for a pleasurable motoring experience. As an aside I think the Atlas ohc 6 is GM’s next best engine.
GM’s legacy OHV engines are far from dinosaurs. In fact, they are the best overall engines in your stable. I doubt many would argue this point. The arguments that GM’s engine technology is dated are twenty years old. If you are still worrying about that concern, I’d say you are quite insulated from the realities of the auto consumer mind. As it pertains to engines, it’s GM’s newer OHC engines that are actually lacking. Older engine designs are better at GM? Heh? NVH and overall refinement of your newer 4s and 6s are sorely lacking compared to best of breed competitive engines in similarly priced vehicles.
All of that said, I’m not sure the average consumer cares if you put a camel under the hood. I don’t care if my electric company uses GE power equipment. People want a package or a total positive experience. All but the elite aficionados don’t care what’s under the hood. And the ones that do are likely to be fans of GM’s legacy OHV engines.
I have the3 6.0L Vortec OHV V-8 in my ‘02 Denali XL. Perfect combination of performance, reliability, broad torque range and most importantly, driveability. I love that engine and love the technical advances made with the OHV engine by GM. Continue to advance it—make it more fuel efficient, make hybrids with it, please.
Steven
Pushrod engines… great torque, less complexity typically equating to lower failure rates and less expensive to build. All good things and laudable in a new engine. The marketing problem, not an actual problem, is that when you think GM pushrod in a high volume car, you think 3800-genration “who knows how many” with its roots going back to the Eisenhower era. The Corvette and the Hemi in the 300C don’t get vilified for using pushrod’s because they are “new engines designs” (you could make an argument about the Vette small block V8 isn’t new, but you know what I mean) while the evolution of the 3.8 still markets as ancient technology. The issue isn’t the technology as much as the marketing problem of such an old engine.
Seldom do the enthusiast pundits pay much attention to torque curves. Pushrod engines seem to develope mucho torque at low RPM. This translates to quick of the start line. Fun to Drive, too.
Think about torque!
It’s so stupid when people bash pushrod engines without knowing what they’re talking about. There’s nothing inherently better or more high-tech about overhead cams, its just another way to acuate the valves. I’ve owned many engines of both varities and they all have their strengths and weaknesses. Don’t give up on pushrods, just get the word out the OHV motors can be just as advanced as OHCs.
The 3800 V6 may be an old engine but it is a good one. An excellent power and torque curve and good gas mileage. This engine has proved to be very reliable and durable.
I’ve had OHC engines that were only so-so; the ‘83 Camry I drove broke its belt several times and was a gutless wonder
above 4000 rpm.
By comparison, the OHV Engine in my ‘04 Malibu proved a pleasant surprise, providing good from-start torque and better than expected fuel economy (with regular fuel yet!). Only its iron-block weight and top rpm buzz/loss of power reveal its old Citation’s orgins.
Hopefully GM can add aluminum blocks and a little more top end power to these mainstream engines. Not all of us wish to go “SS Bling Bling” just to get a better motor!
And, to repeat, please educate your service departments better about these products you sell – they cannot find TSB’s to save their lives!
You can’t argue with the facts about these engines. 1. Reliability. 2.Great power/torque. 3. Great gas mileage. What else could you want? Well I think some people like (and want) overhead cams because they are percieved to be more high tech and up to date.
I admire GM for recreating the fabled Small Block Chevy engine. I’m glad they did. The engine should hold it’s own untill they do away with Camshafts altogether.
I am an engineer working for a major American automotive company, and a member of SAE.
Thanks for the link.
I also thought OHC was all the rage, and now I currently have an older Chevrolet with a 350 and a newer Ford product with a 4.6 OHC. I will stick with OHV for all future purposes due to a lower power curve. I’m not the kind who likes to rev the engine up to 4500 RPM just to get going. Keep doing OHV Chevy!
The problems with GM isn’t the engines, it’s the cars those engines get put in.
Cripes, the CTS beat the 300 C to market by how many years? Why is it nobody recognized why it was a success with that lousy Opel engine? The CTS should have bled down. The variants should be on the market now.
Look at how much people are willing to pay for a good car around a good engine. The CTS-V and the Corvette show it.
Use whatever engine design you want, as long as the emissions are reasonably low, the horsepower is ridiculously high, and you put them in good looking rear wheel drive cars that people like me can afford!
If the Impala was a rear driver, I’d already own one. If the STS was about $35k cheaper, I’d already own one. If you brought the GTO to Canada, I’d probably buy one. But until then, I’m sticking to my ‘89 Caprice. D**n I’m sick of that car.
There’s still plenty more power (HP and Torque) that can be gotten out of pushrod engines. I think the new 3.9L V-6 in the Pontiac G6 is using some new technolgy. I’m looking forward to buying a Corvette with a direct gas injection, 3-valves per cylinder, and variable cam-phasing OHV V-8 someday.
I understand the merits of pushrod OHV engines, but the downside is noise, vibration and harshness. Pushrods simply don’t compare favorably to OHC multivalves in that regard, especially at high revs. Understanding this reality, practically the entire automotive world — save GM — has long since abandoned pushrods in favor of multivalvers. My 2004 Rendevous with its 3.4-liter pushrod V-6 is a nice car — until you put the pedal to the mat. That’s when the little OHV blurts an alarming noise akin to gravel being pulverized in an Osterizer. Try flooring a V-6 Toyota, BMW or Mercedes-Benz product, and you get quite the opposite: a creamy, almost silent rush of power that’s a pleasant sensation. You can hawk the merits of pushrod engines until the cows come home, but I’m pretty sure that a car owner prefers to have his or her senses rewarded, not offended. I’d make an exception for the fabulous GM small-block V-8, but please do GM a favor and phase out the other pushrods — quickly.
Thanks,
John
The article IMHO nails it. In fact, I think it understates the inherent advantages of pushrods. I really like the sound and the torque of the pushrods over any OHC engines. I can’t imagine any “muscle car” without a pushrod. Go to any Nascar race and tell me that the pushrods sound “less refined and sophisticated”. I really think it is the one main advantage that the domestics have over their foreign rivals. Can any manufacturer match the torque, power and gas mileage of the new Corvette? In a word, no. Play to your strengths– Pushrods!!
Funny how no one in the press complains about the DaimlerChrysler HEMI being a pushrod engine. Maybe it’s more of how a pushrod engine is marketed than the fact that it is a pushrod engine!
Pushrod motors are good for some uses and buying segments. But most leading automotive opinion-leaders and influencers have gone beyond push-rod, and now look to BMW, Toyota, and Honda for the class-leading engines and technologies. It is time for GM to become a leader again.
Yes, there are good things about pushrods, most notably the gobs of low-end torque a good pushrod engine can churn out. The venerable 3800 is one example. And GMs classic pushrod V-8s need apologize to no one.
But I have to tell you, as the owner of an Intrigue with the silky-smooth and rev-happy 3.5 Shortstar, those are the kind of engines GM needs to make more of. Having had several rental Centurys and Impalas with the 3.1 and 3.4 pushrod V-6, those engines do GM a real disservice. They are buzzy, noisy, and simply not very good. Maybe V-6s need more advanced technologies to work well, I dunno.
GM needs to get with the program (and the rest of the industry). You cannot be considered world-class with engines like the 3.4 in the main part of your fleet.
OK, GM: market ‘em without seeming so darned defensive, huh? Pick some of their better attributes and push them! Do something slightly ahead of the curve engineering-wise, and promote the heck out of it. But stop saying: they’re good enough for dullard customers!
I don’t have any problems with GM using an OHV, I mean, if it ain’t broke, don’t fix it. It’s not like your average consumer is going to mind much as they probably don’t know what type of engine their car has. They just care that it works. I think Mark is right when he says that your problem is that you don’t counter the criticism and market the OHV designs…
But really Bob, is this supposed to be some sort of smokescreen because you’re too afraid to actually answer our questions/comments from the last topic? TELL US ABOUT THE RWD CAMAROS!!! Remember the “nostalgia phenomenom” you were talking about last week??? Tell us what GM is doing about this…
To give an embarrasingly non-technical point of view, My 2003 Rendevous had a 3.4 V-6 (OHV?) and my current 2005 Rendevous has the 3.6 DOHC V-6 (OHC?). I don’t notice the difference, but I can say I liked/like both engines. Both had/have enough pick up for me and I never noticed more or less noise at high speeds. To add my $0.02, I personally would say if it isn’t broken, don’t fix it. My husband has always praised the 3800 V-6. But then again he has automotive knowledge. The general public, outside of car enthusiasts, doesn’t. They pretty much go by word of mouth or if we are lucky, they test drive the car. I agree that the problem is marketing and I’m not sure how to get through to the general public on this one, but I’d be having some focus groups really come up with some innovative ideas if you want to keep the technology alive. It would be a shame to lose it just because foreign car companies don’t embrace it.
Push Rod Verses OHC
No brainer. Mileage and emissions go hand in hand and the big bugaboo there is weight or mass of the moving object. Ohc engines have heads that weigh as much as their brothers entire ohv engines of equal torque. Ohv engines made of the same materials as ohc weigh less and the only time ohc shines is when it’s reving and making it’s worst MPG because of parasitic drag. Todays economy is happening at very low RPM and therefore does not need the extra valves and weight of the hitech engines that scream so well. I’d like to see EPA regulations be simplified down to one regulation. Everyone uses a 1000cc engine and anything goes. the ones that do it right will sell cars. Do you know how much can be had from 1000 cc / Staged tourbos?
OHV, hey its the 21st century !
If people want stop light low end torque they can do that in some 4 banger but for a sports car you want power throughout the powerband and I find it interesting people who never owned multi cam engines claiming how great OHV is.
Try taking even the new LS7 and get to 7,000 RPMs and keep it there for 100 miles like in a Open Road Race.
Now do the same in a 1990 ZR-1 with a LT-5 and you see what I mean, the OHV is not even close to what the GM/Lotus LT-5 did and still does with over 130,000 miles on the engine which is a bullet.
GM did not break several world speed records with a OHV engine they did it with the LT-5 and they won many a race with the Olds engine, not with pushrods.
In the end nameplates will have to merge into DOD engines and meet federal and CAFE requirements.
People are confusing things here.
OHC has a huge advantage: Because the valve train is much lighter, not having to push those heavy, long pushrods, the engine can spin up to higher RPM. That is really ALL, and EVERYTHING, and the ONLY thing which OHC gives over OHV.
But it IS a huge advantage, as now the engines can spin to much higher RPM, making considerably more power without increasing weight or displacement.
It also makes it easier to do variable valve timing, but isn’t esesntial, you can do VVT pushrods. (But VVT is the subject of another rant. It’s good for another 10% more power: Compare the Duractec Ford V6 with the Mazdafied version in the Mazda6).
The GM OHV engines get more torque (but it is really thrust that you care about anyway) simply because they CAN’T revv to high RPM, so you have to tune the engine for low RPM operation.
Thus the engines, by their nature, must be in a milder, low power tune. Calling this a “feature” is great marketing.
But give me a Mazdafied-Ford OHC combined with a 6 speed auto over GM’s OHV with a 4 speed. And someone who test drives both back to back will probably chose the Mazda version over the GM. They may not know what the words mean, but they can tell the difference when they step on the “go” pedal.
The Editor wrote: “We’re not sure exactly who The Auto Prophet is”
==============================
We wait 30+ years to get Deep Throat identified and you have to come up with another “unidentified source” this fast???
Geez, give us some breathing room!
The Vortec 5300 which will be used in the 9-7x and also is being used in several other trucks ans suvs. The engine with the flexifuel (E85) version which is being used in the GMC Sierra 2006 would be perfect for the Swedish market if GM take the descision to take the 9-7x to Europe. Flexifuel vehicles get tax rebates and free parking in the “big” cities here in Sweden. We got a flexifuel version of the 9-5 which now are the most sold version of the 9-5 right now here in Sweden.
I really don’t care if it has pushrods or not, I just want an engine that has power to do what I need it to do and fuel economy.
The Big block and small block OHV V8’s from GM are IMO the best engines ever, the sound of them is something worth being there for.
As some people have said, about how the engine is noisy over say, 4 grand, how often does the Majority’s of auto backed cars go over 4 grand? not very often, some don’t even go above 3 grand.
In Australia, we had the 3.8 up until the middle of last year when it was replaced with the Global 3.6 DOHC motor, it could sound better, but it’s a definite improvment, it’s smoother and a lot nicer, even if most models are still stuck with the TH700 gearbox, while only two get the new 5 speed Auto, something GM needs to fix.
I’m quite dissapointed at GM now, they have decided to drop the Zeta platform for America, leaving Holden Australia out in the cold, thanks a lot, 4×4’s are not the be all and end all of vehichles, introducing large/medium RWD V6 and V8 powered cars, in an attempt to gain back some of the younger market, who might not always want a powerful RWD car, but wouldn’t mind one, or knowing that it can be powerful even. Compare the sales of the Aussie Ford Falcon and Commodore to the FWD Camry’s and Magna’s and you can see that they sell more, some is loyalty, the rest is because of good dynamics and because they are RWD!!
The Zeta platform would and still could host these new cars, if GM had a large RWD car again, based on a modern design, I’m sure you would gain a lot of sales, just let us Aussie’s have an Australian made Monaro without any need to please the American market!
Thank you for your time,
Disgruntled GM Fan,
Alex.
Dear Mr. Lutz;
Well a LOT has happened since my first post earlier this week!
While I hate to hear of ANYONE losing their job, I think that this is a case of GM having to do an amputation to save an ailing patient for a stong recovery.
After all if (god forbid!) GM fails, no one will have a job, will they?
Our dream of driving a built in north America GM car again will be dashed.
All I say is that perhaps the number needs to be more like 50 to 55K job reduction in the short term with a more aggressive schedule than announced, albeit short term pain for long term gain…
I have to say a few things here. PUSHROD Related!
My main point being that those blogging here are those that want to BUY GM products again.
The cars they want built NOW may not be profit leaders (may even be loss leaders) but will vastly boost the image of GM where it matters, on the streets and in the homes and garages of North America where people are no longer buying GM and now see automotive “icons” as BMW’s, Hondas (gag…), Porsches, Infiniti’s and so on.
How so? I like to explain it as “product exposure” ( or lack thereof),I was brought home from the hospital in a classic Pontiac.
Kids who are eager to have cool wheels now were brought home from the hospital in new 1987 Honda Accord turn 18 this year!
They have NEVER seen a GREAT car from GM ruling the street except perhaps at a car show or museum.
They actually think (through clever marketing and what is typically driven on the street today and they are constantly exposed to ) that a 4 cylinder Honda with “NOS” ( how I hate that term) is a fast and powerful, sporty ride!!!
(Yikes!)
Yes… They have experienced the internet, every video game out there and have piercings and tatoos BUT they have never experinced on of the most real sensations there is… TORQUE!
These 4-bangers wound out at 9 grand have no torque but in the “vitual reality” world that they live in with instant information, cars that are lame have become icons and they buy them in droves!
It is up to GM to produce and get out on the street a V8 torque monster ( oh for the days of the ‘70 buick Stage 1, 510 ft. lbs of torque off the showroom floor!) that is very Afforable (Hmmm…subsidized in the 1st year of production with easy asscess in everytown USA and several dozen being given to youth celebrities and opinion makers, why not?) and creates a HIGH Performance profile for GM with the PRESENT generation!
I think this is the way to go and while the Cobalt SS is a vaild “me too” effort, this is NOT a musclecar that will turn heads and change opinions…the way education on torque by your faithful and newly converted in the street will!!!
Now (finally..lol) on to my point about Pushrod engines!
Ed Cole launched the small block chevy onto the public in 1955 and the world has never been the same!
The hallmark of this engine is “Simplicty” that lives onto this day.
When GM engineering needs to solve a problem it comes up with the safety pin, the Japanese and Germans propose the Space Shuttle to accomplish the same goal!
Therefore keep it simple, price it RIGHT (i.e. affordable or even cheap for joe average) and keep the pushrods!
…and to end on a positive note
Recent GM Homeruns:
Corvettes C5 and C6!
World class and priced beyond the average man but fairly when compared to the competition
Chevy Silverado!
However, you do need a 1500 with the 6.0L non SS stripper priced real low, this would sell like proverbial hotcakes.
Pontiac Grand Prix.
All Suburbans.
World leader
GTO!
BUT you need raise their profile, offer more and in Canada and the price point needs to come down to the Mustang (did I say 1 year subsidy to get them out there??)
I know times are tough but many people are counting on you to do bold things like the afore-mentionned Cole did in the storied history of GM!
Good Luck, we will be watching and cheering you on!
Derek Goldthorp, Editor
Torque and RPM.com
Perceived & real reliability is probably one of the best reasons to keep using the pushrod motor in bread & butter cars. The older overhead cam vehicles are now seeing the need to have their belts or chains replaced at substantial cost & inconvenience to the owner. They will not consider this normal maintenance especially since the same person probably does not know the difference between a push rod versus OHC motor. Now throw in the lower manufacturing cost advantage…No brainer, keep the push rod motor.
I see the need for OHC motors for peformance models only.
I think the best comparison may be right in the GM family.
My Buick LaCrosse CSX with the 3.6 DOHC gets 2 mpg average LESS than the Pontiac GP supercharged 3.8 it replaced, both over thousands of miles on the same driving cycle. Not sure how the performance numbers stack up, but the GP felt stronger, too, at least in stop and go driving.
Well, let’s see here…I’ve owned a Chevy 302 V8, 350V8, actually bought a 1975 Chevy Cosworth Twin Cam Vega, had two Olds with the 3.4 DOHC V6’s, an LT1 and now an LS2 in the form of a 2005 GTO. I’m one of those rare people that actually do care about the engine in my vehicle and the LS2 is hands-down the finest, most powerful engine I’ve ever had the pleasure to enjoy. Plus, I’m averaging over 20mpg with 400hp under the hood. If you could do that with OHVs fine, but I doubt it.
My wife drives the Maxima and is having no luck prying the LS2-powered GTO from my hands. Does that answer the question? By the way, thank you Bob Lutz for this GTO. I would not have purchased a GM product if this did not exist!
Honestly, why can’t we just have increased development/refinement of the existing OHV engines, and a silky-smooth, high-feature OHC engine available as an option? The Shortstar is (was?) a great engine. Just making it available will appease the critics, the existing engines are good engines for those who like that kind of engine.
I believe the average consumer couldn’t give a Rats behind what the motor is in the car (or care much) as long as it is trouble free, gets excellent gas mileage and sounds terrific under most conditions. You could put camels, horses or gerbils in most peoples cars to make them go and they wouldn’t know the difference.
I have a 2004 Grand Prix 3800 and I have no complaints! I get between 27-32mpg in most of my driving. Lots of torque and low end where the Average American needs it. With speed limits at 70mph and below, whats the point? If it’s a refined pushrod, no big difference. Tho, do get rid of those awful 3.4’s once and for all.
Probably the greatest race engine ever built was the “push rod” 3.43 litre Mercedes-Benz 1994 Indy 500 winner built by Ilmor.
Perhaps GM can put a small block OHV lightweight V8 in the Solstice, as some aftermarketers are promising?
In any event, whatever V8 ends up there will make GM “Kappa Platform” dealers (and the customers who can afford the markups) __VERY HAPPY__!
My comments relate and echo a number of people on this thread: It’s not that OHV are inherently inferior to OHC engines, it’s the driving experience and how that translates into what you feel in the seat of your pants when you’re behind the wheel. GM’s answer is typical, in my mind, of the core problem of why GM is a laggard–it makes product decisions for the wrong reasons: all purely financial, which ironically, ends up costing them financially. Does it matter if the tooling and cost of the engine is completely accounted for if NOBODY is buying the car, except for Hertz and Avis? If Toyota, Honda, Nissan, BMW, Chrysler and Mercedes can invest in new engines every 5-10 years why can’t GM? Why must it keep putting buzzy, rough idlying, low power engines in new cars? If GM is wondering how it got to the state its currently in, look back on all those decisions NOT to invest in new engines and its symptomatic of a systemic culture at GM. This culture also believes, wrongly so, that consumers don’t know or care about what’s under the hood of their Cobalt or LaCrosse or G6. How wrong they are. I think GM feels that it can continue to drop in inferior engines and people won’t notice or care. And this is from the company that once produced 427 Corvettes, SS396 Malibus and SS429 Camaros. How GM lost its way is evidenced in the answer they JUST POSTED on the value of their current OHV engines.
It’s obvious they haven’t driven a 3.0 liter Honda Accord, or BMW lately.
Short hood to ground requirements almost necessitate pushrod over especially DOHC which because of the extra upper parts becomes a taller engine. Sure there are limitations on top end rpms with pushrods but since individual spark plugs are controlled electronically without distributors why could not the next step be electric pushrods or valve actuators and tota;lly eliminate the camshft completely.
Noise and vibration are critical to the customer experience. Smooth, quiet and linear power delivery is the standard expectation. OHV can deliver this, but requires good intake and exhaust manifolds, naturally balanced bank angles, stiff blocks and sophisticated engine mounts, among other things. The end experience is the most important. Demonstrate superiority through results.
John: BMW does that on the engine in the new M5: THe valve are entirely electronically controlled. Very slick technology, it is equivelent to always having the right cam at all times.
On the new 3 series engine where they use it as well, it resulted in +10% performance gains AND +10% mileage.
I think the condescension about what the “average consumer” does and doesn’t care about (by people who obviously don’t consider themselves average consumers) is exactly what got GM in the trouble it is now, causing it to cut 25,000 employees.
Oh, but they are giving the employee discount to everyone now…I’m sure that makes those 25k much more relieved.
GM, stop trying to tell us why we should like what you choose to give us, and start giving people what they want. That’s the only way to make money.
Demand should drive supply, not the other way around.
Repeat After Me: Demand Should Drive Supply
This article, and the attitude of many of the consumers dismissing what they think the “average consumer” wants/understands, seems to assume consumers should just accept whatever GM decides to sell. That’s resulted in another planned layoff of 25,000 w…
Just another vote for high torque at low RPM being more meaningful and valuable where the real world drives almost all of the cars. High RPM torque is too much trouble to get there, while low RPM is there RIGHT NOW.
I think OHV engines are a mixed bag. Good reliable appliances in their old low horsepower models. Brilliant reinvention of an old concept when used with ultralight pushrod materials and variable valve timing.
I am not impressed by high horsepower engines with low torque. My VW Golf 2.0 has a miserable 115 hp but much higher torque, and at lower rpm, than some more modern (multi valve, variable valve timing)engines, and as a result it is very “drivable.”
GM gave us 3.8’s when other manufacturers only had 3.0’s. Guess what, the 3.8 in the Impala moves it quite nicely AND returns superior mileage.
I hope GM continues to update the OHV engines it has. I am quite interested in a Malibu with a vvt 3.5 or, better yet, the vvt 3.9.
On the other hand, when will we see something other than the 4 speed automatic? I realize at this point it has a great durability record, but at this stage in the game, can’t we get both durability PLUS 5 or 6 speeds?
I don’t mind OHV technology. The fact that the last five cars I’ve owned have used OHC engines is not due to any religious conviction about their inherent superiority. GM, as usual, is missing the point if they think their engines are perceived as crude because of their choice of OHV.
I am not referring to GM’s top-of-the-line Cadillac NorthStar or the Corvette. I am referring to the engines in the cars we mere mortals can afford – 4 and 6-cylinders like we find in Chevy Cobalts and Malibus, Pontiac G6s, etc. GM thinks we consumers are asking for the world when we demand butter smooth idle, even power and torque delivery over the whole usable RPM band, quick and predictable throttle response and low noise/vibration/harshness through it all.
These things are no mystery to GM; the NorthStar V8 is a model of refined behavior, so I know GM is capable of instilling these virtues in their engines. Unfortunately for them, so is Honda, Toyota, Volkswagen, Nissan, even Ford and Daimler/Chrysler – in cars residing in that sweet spot between twenty and thirty thousand dollars – the cars we proles can afford!
All this refinement that I and many expatriate former GM owners crave has less to do with the kind of valve gear used than it does with stiff engine blocks, well balanced cranks and cams, low-mass pistons, attention to intake and exhaust tuning, yada, yada, yada… You’ve heard me beat this drum before, but Volkswagen’s yummy VR6 accomplished all this refinement without all the high-tech gimcrackery like variable cam and valve timing. And if my memory doesn’t fail me, I remember the old Ford Fiesta (No, not the Korean-made Festiva, but the small car from the late 70’s made by Ford of Germany.) as having a VERY sweet little 4-cylinder motor, not the grinders still found in modern Saturns and Cobalts. And this jewel of a motor was a very low-tech overhead valve design! A joy to drive as I recall, not a penalty box like the contemporary Chevette.
Make me a V-6 that sings like my Jetta VR6 – in a car in my price range like the Pontiac G6, otherwise a pretty nice car – and I will look seriously at “coming home” to the cars my dad drove and the cars I drove years ago before GM lost its way. It’s not the technology, it’s the execution.
Ummm, why is it GM is always trying to ’splain to us why OHV is better?
For god’s sake, build good 3.0L DOHC V-6’s for once. The existing LS2 and Northstar engines are good fit or thie niche.
But the pushrod I-4’s and V-6’s are just junk.
I’ve driven the 3.8 V-6 in the GP and compared to my Acura 3.2 DOHC V-6, it’s like a tractor engine.
If power vs. engine weight numbers were as heavily marketed and hyped as power vs. displacement, pushrod engines would make a lot more sense to the enthusiast and general public alike.
However, to mirror some previous comments, I’ve never felt that engines were GM’s weakness…
OHV has one large advantage, piston speed, putting out 80% of OHC output at 35 % less piston speed is a life saver for the engine and drive line. Power is excellent for all cars these days, real issue is engine life and cost per mile. I love the 60 degree V-6’s GM builds, they last and are very comfortable to drive. Most 4 valve OHC engines are expensive to purchase and wear faster than OHV engines. Power in traffic is not the issue, comfort and cost is the real question here.
The honda lawn mower engine has an overhead cam. Pushrods were great in the 50,s and 60,s ,but are as ancient as the flat head engine. Gm builds great overhead cam engines , such as th inline 4,5,6 truch engine family and the inline 4 car engine. Push rods create problems for fuel delivery and air flow. Pushrods are faiding lawn mower technology.
People read car magazines for advice.
Car magazines don’t like pushrods.
Therefore, you shouldn’t use them in anything but trucks.
Produce what people want to buy, not what you think people should buy.
And get those d**n 5 and 6 speed automatics in your cars already! What are you waiting for?
For a ho-hum car, who cares what type of motor the car has. All people care about is the performance numbers. HP/TQ and MPG.
And, I really hope GM is chasing down Mercedes and the rest of the German crew, with their camless motor designs.
GM forever. I have no desire to own anything other than me a GM vehicle. I have owned a myriad of vehicles OHV & OHC I fail to understand all the hype for OHC. Every time I have worked on an OHC engine I have hated the baloney involved like the plague. Give a GM RWD full size that is affordable and has plenty of guts for the congested American highways and I am happy.
As a former auto recycle yard owner, I have experienced nearly every vehicle ever sold in the USA and nobody can convince me that anything made in Asia is worth a wooden nickel.
I have a ‘98 Grand Prix w/ a 3800 V6 and I love the torque and fuel economy. When I consider an engine, I want reliability first and foremost. Next to that, I want good power, torque, fuel economy, and price. Exactly how these parameters are obtained aren’t that important to me – I’m results oriented. Many auto enthusiast believe that a high horsepower per liter indicates high tech. Seldom do the car magazine editors consider long-term reliability or cost. After receiving such satisfaction from my GP, I’ll likely have a preference for GM’s pushrod engines when shopping for my next vehicle.
Someone said:
Can any manufacturer match the torque, power and gas mileage of the new Corvette? In a word, no. Play to your strengths– Pushrods!!
I say:
Show me another sports car that has a 6 speed manual with two overdrive gears. There are none! No wonder nobody is beating the vette’s fuel economy. Does anyone else have skip-shift?
One word… C-O-R-V-E-T-T-E. Why is there any argument at all about pushrod engines? Oh I know, it’s not european or Japanese to use pushrod technology. Sorry, what was I thinking. Pushrod is good old fashined Ed Cole inspired Zora tuned ground pounding thunder making torque and hp and now makes 505hp and is so efficient it beats the gas guzzler tax. I’m such a silly American, what was I thinking. This can’t be good technology if it’s still the leader after 50 years. I guess I’ll pull the Vette out and go for a spin down Woodward to change my attitude. Hey Mr Lutz, will you consider putting LS7 or LS2 badges on cars and trucks that use this OLD awesome pride inspiring American PUSHROD technology? Just a thought. It would have been nice to see GM beat Hemi to punch on that one. You had to see that one coming right? GM Badges are nice, keep it up. I saw a Soltice on Woodward the other day – AWESOME. Looking forward to following the new Saturn Skye too. Rock On GM, you’ll get there. Ciao, Bella
Bob,
I am really looking forward to the 3900 G6 coupe with the 6-speed manual.
It shows you taking the pushrod seriously as more than a value engine in vehicles other than sports cars (Corvette, CTS-V) and Trucks with V8s.
I’d love to see GM really push the 3900 V6 with its Variable Valve Timing and Cam Phasing as another flavor of engine.
People value the Mazda Rotary Engine despite a poor fuel economy to power ratio in the RX-8 for instance. If the Pushrod engine was offered as another unique choice for enthusiasts of “Tuner” type V6 coupes – as in the G6 and Monte Carlo (which needs a manual trans for any credibiltiy, the 4-speed wont cut it) – then we could see the Pushrod go from derided to celebrated — beyond the Smallblock, that is.
Good luck on this — the auto media has bowed in aknowledgement of the superiority of the smallblock, and with effort the 3900 might some day get the same kind of praise.
Many people out there INCORRECTLY critize GM’s low-tech approach to engine design and selection. Almost all of what I have read are ONE DIMENSIONAL COMPARISONS, they do not consider all key engine attributes, AND THEREFORE ARE MISLEADING.
People rave about foreign automakers’ 4-valve per cylinder, DOHC V6’s while bashing GM’s age old 2-valve per cylinder OHV V6’s and pushrod V8’s.
Consider the following the next time someone is bashing this a low-tech approach just because its low-tech:
Pushrod vs. DOHC:
GM’s 2V/cyl OHV 3.8L V6 vs. a foreign manufacturer’s DOHC 4V/cyl 2.7L V6″
1) Engine mass: OHV-2V 15% lighter. Simpler valve train.
Packaging size: Similar.
2) Specific power: DOHC-4V 50% better. Based on engine displacement.
3) Low speed BMEP (low rpm specific torque, i.e. off-the-line accel.): OHV-2V ~40% better. Engine power is most strongly correlated to total piston area. I.e. there is not replacement for displacement.
4) BSHC (hydrocarbon emissions) DOHC-4V slightly lower.
5) BSNOx (NOx emissions) OHV-2V ~20% lower.
6) Engine NHV (noise): Similar noise levels.
7) Friction: OHV-2V 30% lower. Lower engine rpm = low piston velocity = less friction.
9) Quality: Similar.
10) Cost: OHV-2V ~50% cheaper, the primary benefit of being low-tech.
11) BSFC (fuel consumption): DOHC-4V 15% better.
As you can see, each engines has its advantages. The DOHC engine do not win in every catagory. Give credit where credit is due. GM’s 3.8L V6 is an impressive engine, despite the pushrods and low technology content.
(Ref. Ward’s World Engines Database)
In Kevin Rypstra’s opinion, I and people like me are “incorrect” in their criticisms of GM’s powerplants, and he states mountains of numbers to prove his case.
I can’t speak for anyone but myself, but I don’t criticize low-tech engine technology on that basis alone. I criticize GM’s execution of it. (Please don’t bring up the Corvette or the high-end Caddies. I’m not interested in cars that cost over 50 grand; I can’t afford them and neither can most others.) The fact is, regardless of the technology involved, GM’s engines in their mid-priced lines – we are talking mostly V-6’s here – simply don’t run as well as those in the similarly priced Japanese and European competition.
I don’t have any issues with GM’s durability or efficiency. But their fours and sixes are just not as smooth, not as quiet, not as refined, not as overall pleasureable and satisfying to drive. And when it comes to these criteria, only MY opinion counts, because I am the one plunking down MY thirty large! But apparently, I’m not alone, if one can tell by the popularity of cars like the Camry and Accord and by GM’s ever shrinking market share. The buying public’s votes are the only ones that count, whether we are “wrong” or not.
And since there is no evidence in my long ownership experiences that the Japanese and European engines are any LESS durable, I will go for the cars that are more enjoyable to sit in and drive, WHATEVER the means their makers use to achieve that superiority.
GM can use OHV technology until the sun collapses into a neutron star for all I care. If they can equal or beat their competition using low-tech, bless them! But I won’t buy their cars until they do.
I agree with the previous article from William Irving. GM should be focusing on what the consumer wants. GM should be focusing on giving them engines that are as smooth, quiet, refined, and overall pleasureable and satisfying to drive as the best in class. If GM can do that with OHV technology, fine. If not, then GM better start working on DOHC engines.
Push rod engines may have their merits, but the consumer wants a quiet, smooth ride. Some of GM’s cars (the Grand Prix comes to mind) sound like lawn mowers.
I recently had a rental Dodge Durango with a Hemi in Colorado. After 2,000 miles of driving, the roaring sound of a push-rod engine got to be downright annoying.
For pleasurable driving, the Honda 4 and 6 cyl engines are tough to beat. GM needs to figure out how to give it’s customers a similar experience.
Focus on what the customer wants, not what you already have in your parts bin!
I am definitely a gear head. IMHO pushrod engines are where flathead engines were 50+ years ago. The flathead can be made much smaller and lighter than the OHV because the heads could be very small. The valve train is about as simple as you can get. Therefore, we should be using the flathead design. However, the serpentine path that the air fuel mixture had to take to get into the combustion chambers meant that it couldn’t adequately charge the cylinders at higher rpm.
Over time, most people came to realize the advantages of the pushrod engines. However, the problem with pushrod engines is the pushrods. Like the flathead, the problem is serpentine path that the air fuel mixture must take to the cylinders. As with the flathead, another technology became practical that could better charge the cylinders at higher RPM because there were no pushrods to dictate the path of the fuel-air mixture. That design is the OHC. While the technological advantages of the OHC had been clear from racing experience, these advantages alone were not enough to propel OHC engines to the masses.
A couple of other factors came along that changed what we were after in an engine. One was front wheel drive, and the other was emissions. The generous 4.4″ bore spacing that we enjoyed with the small block V8s made it too wide to fit in a side-winder front wheel drive car. Making the bore spacing smaller means smaller cylinders, smaller valves, and less room between pushrods for the intake and exhaust ports. This results in fewer cubic inches to work with that you cannot charge as well. The other side is emissions. The way to reduce unburned hydrocarbons is to keep the cylinder pressures higher. The only way to do that is to generate the same horsepower with fewer cubic inches.
Smaller bores means longer strokes to maintain some of the engine displacement size. There is also less room for valves, so you need more of them. Here the OHC engines get a bum rap. For instance, the 5.7 Ford has a 4.165 stroke and the V10s have a 4.17 stroke, which is longer than ANY other OHV engine that Ford or GM makes. Furthermore, the rod must be longer to maintain the rod to stroke ratio in order to reduce the side thrust on the piston caused by the longer stroke. That height has to go somewhere. Thus, it’s not the cam that makes the biggest difference in the physical size of today’s OHC engines. The LT5 DOHC heads and 3.1 DOHC heads designed by Lotus, fit fine under the low hood of the 1990-1995 Corvette and the other GM vehicles.
What we are looking at today are OHC engines that were not really designed to be racing engines. For racing you would want to dig up a LT5 where it has a good rod length to stroke ratio, and was not very tall.
Technology has gotten better. Winnebago now uses the Ford modular series as their recommended platform, and the reason isn’t gas mileage. Somehow Ford made that engine with its crazy piston speed, survive running at or near full power hour after hour, and Winnebago is getting unusually long engine life from them.
Personally I think that useful life of cams is limited because of their inability to adjust to engine rpm and load. VVT, even BMW’s, is crude crutch that is fraught with compromises. In my opinion, the real fix to controlling valve timing is electronically, just as it is done today with fuel injection. However, there is another engine that there is a lot of investing going on with, and that is the 2-cycle engine. The 2 cycle engine has been used for years in everything from chain saws, to tug boats, to trains, to GM Diesel truck engines. When I read what they have done with it, and the emissions and efficiency problems that they have solved, it may hold the most potential of all. It too has benefited from the electronic age.
Jack T.
This really makes me laugh, A bunch of guys who could not change a spark plug if their lives depended on it are telling us what is better pushrod or ohc, They have no clue what makes an engine perform, The OHC is by far the WORST option, The long chains required to run the cams make it impossible to maintain the exact cam timing needed to produce real power and RPM. The chains strech causing timing changes as well as transfer harmfull vibrations thru the valvetrain. All of the most powerfull engines in the world are pushrod. A perfect example is NHRA Top Fuel dragsters and funnycars, they have 500 cubic inch pushrod engines that produce over 7000 horsepower @ 8000 rpm. Drag racers will kill for one tenth of a horsepower gain and if OHC were better they would be using them, 99% of all drag cars are pushrod. No other form of racing can compare to the Rpm, Torqe and Horsepower of the modern pushrod drag engines.
And I am still trying to figure out how this is going to get the CAMARO and other RWD cars on the showroom floors sooner? I go by the CHEVY dealer every day to see if any arrived the night before, Unfortunately none have made it there yet.
I can’t believe GM still thinks it can survive by marketing good engines. They must offer what are seen to be good engines.
Whatever the merits of pushrods they are perceived as inferior technology. Worse than inferior – OLD. And that doesn’t sell.
Perfectly adequate 4 speed ATs also won’t sell. Get, at least, that fifth gear in there!
Geez! How many decades have they wasted? Only one is left!
I have no problem with the pushrod in my new g6. what i have a problem with is the 4-speed auto. that engine needs another gear to work with and the whole package would be much better appreciated.
Biodiesel should be the next fuel of GM and USA. I wish GM would invest more in research and deployment.
http://www.statesmanjournal.com/apps/pbcs.dll/article?AID=/20050708/BUSINESS/507080316/1040
It is better than hydrogen.
When I saw the LaCrosse, all I could do was ask myself “Is GM suicidal?” Who wants to buy the perfect ‘98 Taurus? You don’t have to be a car nut to sense that this car is stale. When people — even 68 year olds — spend $30,000 on a car, they want the neighbors to say Wow, what is that? They want to stare at it and be excited. You guys keep starting with a blank piece of paper and coming up with blanks. Cadillac, though not my personal style, is excellent. It has a look that’s identifyable from down the block. Plus, the public [not just kids] LIKES it.
How about some body sculpture, 2-toning, 3-toning, textured exterior surfaces, even a tasteful fin? Dare I say it — how about some IMAGINATION?????
Pushrods are fine. The question is whether the execution is 21st century, or much earlier. LS7 is a 21st century engine. Some others are yesterday’s news. The Chrysler hemi is a success because Chrysler understood the brand equity in the term “hemi”. GM squandered the brand equity in “GTO” and “SS”–among others.
Agree with some that even older engines can benefit from 21st century transmissions.
GM has all the components and talent–they just can’t execute.Don’t understand why, but it will be the death of them.
Graeme Sackrison
Lacey, WA
it’s hard to give people what they want when they don’t know what they want. all people care for is novelty; if it’s ‘new and improved’ it will sell. just make a ‘new and improved’ pushrod motor:)
j.toering’s rant is full of incorrect statements. the small block can’t fit in a fwd vehicle? go buy an ss monte carlo.
hc emissions is related to bmep? ok then. we all agree that ohc engines make more hp because they rev higher. but at low rpm, ohvs make the same or more torque…which means higher bmep. so…you’re in fact saying that ohv engines have lower hc emissions? what’s it gonna be? fwiw, most dohcs don’t rev past 6500 rpm – the same as the ls2.
j roevner: march 1, 1990 a basically stock zr-1 driven by john heinricy broke the 24 hr, 5000km and 5000mile endurance records. it did this at 5500 rpm, not at full throttle.
the ls7 is a detuned endurance race motor. whether it can last a race is not in question. and i almost creamed my pants when i heard them start up the z06 at the 2005 sae show! no lawn mowers here!
fwiw, the 1990 zr-1 with the lt-5 cost $59,275. the 2006 z06 costs $65,800. even the 2004 z06 trounces the zr-1 for less money (disregarding inflation).
nascars rev to 9000 rpm. it’s not the pushrods that limit rpm. it’s the big intake valve, and the hydraulic lifters. and the ports on the ls2 are arrow straight…i don’t know how anyone can say that the intake tract is serpentine. get a clue!
Mr. Lutz, i want to redesign the 8100. i know i can do good things.
Dennis says; “if OHC were better they would be using them, 99% of all drag cars are pushrod”. But I don’t drag race.
Clearly “better” is a highly subjective term. Isn’t the public increasingly buying OHC because of marketing or supposed reliability, or some other subjective quality?
My guess is that no engine type is universally “better” but rather very dependent upon its intended use and equally the buyer’s awareness of the advantages and disadvantages – making this very series of comments invaluable.
To further my point – I once owned good old “American technology” – a Miller cycle engine! In certain environments, like those with high cost fuel, it could be deemed the best engine.
When ever this convo comes up I keep hearing BHP/L about one of the most useless spec out there. There is alot more to a car then its Horsepower to liter. Comparing the BMW 5.0L V-10 to GMs 7.0L V-8 they both make about the same power. However the vette motor is some 150pounds lighter, more compact, more fuel efficent, and cheaper to build whats not to like there.
also I keep hearing about NVH being a problem with push rod cars. Im not denying that right now there are more engineer hurldes to over come with pushrod engines in this area but we have come a long way. The Newer Buick that just came out was rated the quietest car made with its 3800. NVH that the driver notices can be greatly effected by the car and you never have to know it.
The fact is that there is only one or two reasons to pick OHC over OHV but alot of reasons to pick OHV over OHC.
Come on gentleman the issue is not how outdated the pushrod engine is. The issue is that there truly has not really been much refinement. It’s still an engine with alot of rotating mass and overhead cam eliminates some of that mass. Translation less weight, less to go wrong, less power lost pushing push rods and less engine mass. However, any piston engine is outdated. The revised rotary engine and ideas such as the demi-turbine engine should be embraced as these engines put out just as much horsepower with half or less weight and rotating mass as a comparable piston engine. It’s all about efficiency and the piston engine is an inefficient dinosaur.
Do away with the cams and the belts and what not and just put electronic actuators.
power (energy) comes from fuel. the best and worst engines aren’t that much different in power from fuel. several decades ago an aircraft pushrod engine got .33 BSFC at 75% power. very few have equaled or exceeded this regardless oh technology
I want an engine that is not only powerful but reliable. The 3800 is an excellent engine and the minor improvements and upgrades as it ascended from Series one to two and so on are welcome and they need to be kept refined every once in a while. The simpler the engine, the easier it is to fix and the less chance there is that things would break.
But with that aside, as long as GM does not return the Bonneville or bring back the other cars that have given GM recognition such as the Firebird or Camaro, then I will not be a returning customer no matter what technology the engine has. And they have to be at an affordable price. I was really rooting for you guys, but after axing 3 legends and missing the mark on the GTO’s styling I have lost all respect for GM. All of those cars I would have considered buying after getting out of college. As others have said, its not the tech but execution and you guys just keep shooting yourselves in the foot.
Pushrods have nothing at all to do with the torque supplied by an engine. That is governed by valve timing, cam profile and stroke length.
While the argument that having OHC adds more things to go wrong is also a fallacy. Intrinsicly an OHC enginge has less moving parts, and those parts only rotate.
The issues involved with timing belts can be summed up as costs vs benifits.
A timing belt is very light, hence it has a far lower resistance to changes in engine revs, so the engine will spin up faster.
A timing belt needs regular replacement, but chain drives need more regular adjustment.
A timing belt can fail, any moving part can fail.
Gear drives are more reliable than timing belts, they also add more mass and more cost to the engine.
Hence lightweight short stroke high revving engines benifit a lot from timing belts. Half Ton V8’s less so.
It is a LOT easier to add more valves to the head design on an OHC engine. On a large capacity low revving engine that may not be needed. But it can be used to improve peak power, torque and fuel economy.
In Australia GM used the 3.8L v6 in its flagship car as the standard motor. However GM also used a 3.5L OCH motor in its SUV. The SUV developed more power and torque, ran quieter and used less fuel.
Not something GM advertised.
The costs involved in GM developing and re-tooling for OHC engines would be huge. The need for them to do so is reduced while their primary competitors have not done so.
the one that comes up with a heated windshield would be forever blessed.
Overhead camshaft technology is hardly new. It first started appearing 80 years ago in the mid-1920’s.
To give you a better idea of how old OHC is,
the era of the steam locomotive would last another 3 decades. The 8-track tape player wouldn’t be invented for almost 40 years.
Keep that in mind the next time you hear somebody crow about that “modern” overhead camshaft.
If you compare typical american and european engines you immediately notice a significant difference in displacement w/o a comparable difference in performance. Why is the american car industry preferring larger displacements? Big-block = heavy, expensive, poor consumption.
I’ve seen some very interesting developments with a VVT system for OHV engines. It was entirely mechanical and it provided cylinder deactivation as well as infinitely variable lift and duration on both intake and exhaust. And it all fit within the existing size envelope of a SB Chevy engine.
Hi all!
Looks good! Very useful, good stuff. Good resources here. Thanks much!
Bye
I’ve read this list of statements with a very open mind stand point, which is hard for me to do since I have been a factory trained GM Technician for over 30 years. I have all the latest technical training available to me and enjoy the opportunity to keep these cars on the street.
My problem with all of these statements is the fact that not a single one talks about the truth with GM engines — at all.
My business sells a variety of brands, and over the last 10 years I have seen a massive decline in the amount of work that gets scheduled for me to perform. I see 100,000 mile tune-ups, 150,000 mile cooling system services, oil-life monitors allowing engines to go 5 to 7000 miles on oil changes with no adverse effects, very few problems with GM cars as a whole and those we do deal with are mostly related to computer reprogramming.
My job status seems very questionable at best. If power, performance, quietness, lack of vibration and overall experience are your only concern, maybe you should be considering the upkeep and maintenance that you are shelling out for. If foreign cars can do any better than GM from that stand point then I applaud them. I still believe we sell one of the best values on the road today in the Chevrolet Impala. Great ride, Great handling, low maintenance, low cost, great mileage, Great car from any respect.
Oh, woops, it sounds like a lawn mower, by the way, most mowers which I’ve worked on were not push rod engines in fact.
I respect all of these opinions and realize the only one that matters is your own. But unless you’ve driven a newer GM car more than over a weekend, you can’t honestly pass judgement as to the vehicle.
To each his own, but Toyota, Bmw, Honda and so on, only make cars like they make, and if you like them you won’t change any more than I will, give me GM or nothing.
As far as “Old” technology, anyone that knows todays GM pushrod engines should realize that there has been as much techology change in push rod engines today than any OHC engine. The small block alone has undergone 3 generations of updates, all of which are keeping them competitive with all the OHC engines except maybe for what some of you seem to call that “lawn mower sound’. That sound is apparently music to some of our ears.
How many truck engines are using OHC engines? It makes me wonder why so few are OHC. Hum, it must have to do with torque…..
GM 4 cylinders on the other hand have enjoyed a great improvement in all categories and the 2.2 Ecotec is a good example of GM’s committment to the OHC generation. GM also invested in OHC in the 4, 5 and inline 6 cyl. OHC engines in the small truck market.
I do agree with many of you, that GM has done a poor job of competing in marketing. I think part of the problem is the same thing that has hindered them in some racing venues. The lack of money invested tends to limit availability of good intelligent employees. As younger companies travel the path of expansion to realize the benfits of market share, they have paid their sharehloders very well. Those shareholders are enjoying a new income and haven’t had to try to revive a slipping income. The fact that American manufacturers have sheltered, protected and squandered there past incomes, they have all lost site of the fact that they really need to back up and face facts that they will have to spend some of that income to purchase the intelligence again to regain competitive attitudes.
One more thing, I own an 08 Impala SS, 300 hp. sounds like a V-8 through the dual exhaust, runs like a bear at any Rpm and I’d run any foreign car out there that is factory stock, and I won’t tune it up until it has over 100,000 miles.
I do truly hope that the greatest auto manufacturer in the history of the United States and the World, hasn’t given up completely on us yet, and there will be even better to come.
One last comment, my recent training has been on the lastest 5 and 6speed auto transmissions. At this point they are for small engines only, the time they take may seem long, but development of new transmissions for high torque engines is not a quick and easy task when done properly. The 4T60 and 4T80 are good examples of things done right, and I can only hope that the time invested in new transmissions will prove to be an intelligent one. After all, the Allison has done nothing but improve the ability of many trucks of extreme power levels for the world. GM helped develop that transmission for trucks. Thanks GM.
Thanks for our Soldiers and their sacrifices for giving us the ability to sit on computers and express our opinions as we do!!!!!!!!!!!!!!!!!!
OHC cam may be better if you plan on doing long distance high RPM racing/driving. But for regular everyday city / Highway or drag racing, dollar for dollar dependabilty pushrod will do just fine.
Many countries, european countries mainly, has a tax with base of liter´s engine, never OHV is a good idea. But the concept of OHV is briliant.
I repeat: OHV is real tech, DOHC is ego-tech. in many minds, the size of engines is the liters of capacity… 6.0 L OHV has the size of 4.6 DOHC…. and more torque!