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$800 per unit...
http://autoweek.com/cat_content.mv?port_co...t_code=01028000

GM pushes pushrod engines -- and reaps savings
Engines allow company to save $800 per unit sold


By DAVE GUILFORD | Automotive News

DETROIT -- A key factor in General Motors' ability to play an aggressive price game often goes unnoticed or even draws criticism - GM's heavy use of pushrod engines.

Performance buffs belittle pushrods as crude and outdated. But pushrods - expected to make up 62 percent of the 5.5 million engines GM will sell in North America this model year - save GM roughly $800 per unit against comparable overhead-cam engines, analysts say.

That enables GM to boost incentives, add standard equipment or offer a V-6 cheaper than a competitor's overhead-cam version.

Edward Koerner, vice president for powertrain engineering operations, says pushrods fill the high-volume, price-competitive segment of GM's engine lineup. Targeted at consumers who want a reliable engine but don't care about its inner workings, pushrods "give you some feature-content opportunities," Koerner says
OHV--> :zap: <--OHC
 

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5.7 LITERS AND 405 HP ARE NOTHING TO SNEEZE AT, THE GERMS AND **** CAN TAKE THERE CAMS AND SHOVE THEM....... LOVE THAT NORTHSTAR THOUGH
 

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The simple fact of the matter is that untill they make a v6 or a v8 that CONSISTENTLY revs like a inline 4, then there is no way to justify the cost of ohc cylinder heads on a v6 or v8. Sure they're cool, and high tech, but what happens when you have a problem with a cam?? Are you just going to swap one?? No, because the others aren't far behind. And you can buy a cam, set of lifters, and a set of pushrods and rockers for the alot less money as four camshafts for the other engines. The Ford 4.6 camshafts run like 5-800 dollars apiece, and no, that was not a typo. tell me that you're still happy with your ohc engine when you're paying 2000-3200 dollars for camshafts, and your buddy can hold the other 1200-2500 dollars he saved and spend it on other upgrades or repairs. On a four cylinder, the costs come more in line with the benefits. You need the extra RPM that a OHC configuration allows, and the single extra cam is closer in cost to the set of rockers, pushrods, and lifters. Which brings us to the genesis of the OHC versus OHV argument. Honda. Honda fans, feeling inadequate and struggling to find something that thier engines have over other popular engines, preach technology. Thier engines use dual cams, are higher tech, and make more horsepower per liter than domestics, at the time. Well, now the domestics have begun to use ohc's in thier 4 cylinder, and some high dollar 6-8 cylinder engines, and have closed the HP per liter gap. The fued is losing steam, and Honda is just losing. I can look at my turbo 3100 with my head held high. It has pushrods, but it also is lacking the lone low tech holdout that still resides inside Honda's high tech Ivory Tower-a distributor.

Talk about low tech.
 

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For instance, GM has pushed the 2004 Pontiac Grand Prix as a performance vehicle. But it is powered by a 3.8-liter pushrod V-6.

That drew the scorn of a reviewer for The New York Times, who contrasted the pushrod to import competitors' "modern, overhead cam, multi-valve engines - many of them with variable valve timing for smoother, more flexible power delivery."


I'll keep my pushrod engine...thank you very much! I've also heard many complaints from the pro-OHC camp saying the 3.8l engine isn't smooth. I prefer my engine to growl and not whine! :)

I've seen so many examples of OHV engines out performing and matching or beating equivalent OHC engines in fuel econ., I don't understand the biased dislike of a modern pushrod engine... Both types of engines have their place. I just get tired of unfounded pushrod bashing! :argue:
 

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I love pushrod engines! The 3.8 is smooth like no other v6, economic and reliabls (should I say bullet-proof?).

The northstar?: altough it's a very nice engine, it kills me that is so small! Why did they had to make it 4.6 instead of 5.7?
I don't want a engine who revs a lot, because I rarely rev it: I need plenty of low end torque, where I use it, at 2k-3k rpm.
 

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Pushrod engines are so much smaller in height than OHC variants, they offer alot of packaging and styling flexibility.

When engines are tuned for midrange, and the V6/V8s rarely rev over 6K, OHC has little benefit. It's mostly marketing.
 

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[chevy ricer] Dood! if Chevy can make 400hp with just 2 valvez per clyinder - when they add 2 more they will get 800 HORSEPOWERZ!! [chevy ricer]

<_<

It cost less to manufacture. It cost less to repair. It lasts longer. Has less valvetrain mass. Doesn't need to rev high to make considerable power. Quiet at speeds. Newer. Umm...yeah....stuff.


The only bad thing i can think of is gas consumption and negitive public opinion. If the gas issue can be fully addressed - then the public has no reason to have a negitive opinion about an engine that preforms just as well as any other.
 

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I thought the article was good. but i am disappointed that nothing was mention about the new tech ohv-3valve cylinder head for small block V8/V6 push rod engines. <_< Louis here.
 

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This is not a sarcastic question though it may seem to be.,, But Im uneducated on engines if you will, and my question is. If Pushrod engines are the best (as you all may agree), How come every other car company has moved onward to cams and such technology? Whats the deal on that? I just don't understand how this makes chevy the better one.

Honestly it seems like chevy could get more out of their engines (as powerful and durable as they already are) by upgrading them into cam and over head valves. (Put a DOCH on the same chevy pushrod engine, thus makeing the engine more efficient.) If that were the case. Would Pushrod still be the best to you, or are you guys just trying to support chevy's old ways?
 

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Lots of mfgs use DOHC because of displacement limits in Japan and Europe. The limits themselves are pretty stupid if you can get the same fuel economy from a 3.0L DOHC and a 3.8L OHV motor. But that's Japan and Europe for ya.
 

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..........hmm...........

On Edmunds Town Hall, I started a thread a while back in the NEWS & VIEWS section entitled "I don't like pushrods, why do you?". I really did hate pushrods (notice the word DID). That forum really started flamewars! But my main point I wanted to try and get across was why does the 3.8/3.4L "pushtec" V6 have to be in almost every GM vehicle. The Grand Prix is a great vehicle, but I really like the VQ in the Maxima. The people on that board would argue that pushrods are better because you don't have to rev high to get all the power but can easily do city driving in the lower RPMs. I thought that was a stupid reason because I, like most people, like to rev their cars. Yea, 2000RPM is really fun! LOL But anyways, I learned that there is a place for both OHC and OHV in this marketplace, but GM shouldn't be using them for ALMOST EVERY VEHICLE, at least if the power is low like the 200HP in the G6. There are just better and smoother (smoothness is a big factor in many families as surveys show) for the money and in the same class. Anyways, I'm excited about the 3.9L VVT OHV in the G6, but that's awhile away.
 

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Originally posted by yoblues@Apr 5 2004, 06:15 PM
Just give me power and reliability the rest of it is BS.
Couldn't have said it better myself. I don't really care how it does it, as long as it does. Personally I think saying that OHC is better/higher tech (who cares...) is for people with slow cars to feel better about themselves. :p
 

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Originally posted by xellow@Apr 5 2004, 05:02 PM
This is not a sarcastic question though it may seem to be.,, But Im uneducated on engines if you will, and my question is. If Pushrod engines are the best (as you all may agree), How come every other car company has moved onward to cams and such technology? Whats the deal on that? I just don't understand how this makes chevy the better one.

Honestly it seems like chevy could get more out of their engines (as powerful and durable as they already are) by upgrading them into cam and over head valves. (Put a DOCH on the same chevy pushrod engine, thus makeing the engine more efficient.) If that were the case. Would Pushrod still be the best to you, or are you guys just trying to support chevy's old ways?
Adding overhead cams (and especially dual overhead cams) to the Chevy LS-1 engine would make it too tall and too wide to fit where it does. It would also become heavier. So you'd have to shrink the displacement to get an engine of the same size. You'd most likely end up with less horsepower and you'd certainly have less torque.

For example, the Ford 4.6l DOHC engine is larger and heavier than the LS-1.

GM has stated that they plan to use DOHC and 4 valves on inline engines.
 

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Oh no! If pushrod motors were so great GM would not have lost so much marketshare over the years. The Malibu was destined to be a runner up when they shoved that trashy 30 yr old 3.5 in it. If you need proof go wrap out a Honda Accords excellent 3.0 abd then a Malibu, or maybe that misfireing stub of a Buick V-8 that disgraces the Grand Prix. There OK for pickups, at least until people get used to the Titan 5.6. Another example of GMs "good enough" attitude.
 

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Pushrods are awesome because they are cheaper. That's the argument here. Cheap is good--I'm sure everybody will agree on that. Pushrod heads don't flow as well as DOHC heads do, generally speaking. Overhead cams allow things that pushrods don't, like variable valve timing. This is good not only for power but also for emissions cleanliness. From a purely design performance standpoint, multiple overhead cams are superior to pushrods. It's the other non-performance aspects of pushrod designs that make them desirable to some. There's no need to go attacking the merits of overhead cams due to defensiveness over pushrod love--or vise versa. I myself love the idea of dual overhead cams but I also appreciate the cheap and easy nature of pushrods since I have a big tripower Pontiac 455 that uses them. Both are good.
 

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Originally posted by free_energy0@Apr 5 2004, 09:58 PM
Oh no! If pushrod motors were so great GM would not have lost so much marketshare over the years. The Malibu was destined to be a runner up when they shoved that trashy 30 yr old 3.5 in it. If you need proof go wrap out a Honda Accords excellent 3.0 abd then a Malibu, or maybe that misfireing stub of a Buick V-8 that disgraces the Grand Prix. There OK for pickups, at least until people get used to the Titan 5.6. Another example of GMs "good enough" attitude.
THe 3.5L in the Malibu is new. THe 3.8L in the GP and LaCrosse is very smoth, good on gas, qualifies as SULEV, and is near bullet proof.

Arrowhead222, the new pushrod 3.9L comimg out in the G6 will have VVT and DoD (something OHC doesn't have). Plus 3 valve heads will be out in the next 1-2 yeas and that should take care of the heads not flowing as well as DOHC problem.
 

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I believe a lot of the NVH issues associated with GM V6s as compared to the best OHC competition has nothing to do with their pushrod configuration. Much of the smoothness of something like a Honda six is the result of countless details in engine balancing, mount design and a whole lot of tuning to get rid of unwanted noise and vibration.

GM could spend a little of the reported $800 per car on that kind of attention. If they did, people might be pleasantly surprised how smooth and nice-sounding a pushrod engine could be.

Certainly on their more expensive V8-powered vehicles, the engines have a stellar reputation for being smooth, powerful and nice-sounding. A little of that attention on the 60 degree V6 engine family would go a long way to convincing people high value doesn't simply mean "cheaper."
 

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Sounds like free energy didn't take his ritalin :lol:

What I think is interesting is that pushrods are having a mini-revival right now. The LS1 series has brought attention to this architecture and the Hemi is further bringing notice to this layout. With 3 valve heads, DoD, and VVT on the way, I believe it is only a matter of time before Ford is forced to realize pushrods are the way to go as well. They've already reduced their DOHC designs to SOHC designs (and gained power doing it) so maybe they will realize no one will ever talk about a 'cammer' the way they talk about a 351 windsor.

I believe when people talk about 'efficiency' and engines, most people don't know what they are talking about. They only want to talk about HP/L which is a pretty meaningless feature. I don't know where poor fuel economy comes from. I challenge you to point out any other 350-405 HP car that gets around 22-24 MPG (combined) like an F-body or 'Vette.

I think most angst against pushrods came from people with over-priced imports that keep getting eaten on the track and the street. They make themselves feel better by shouting, "ineffeciency!!!" at your taillights, as you smoke them and get better gas mileage. :lol:
 
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