Why the pushrods (still)?

[squala]

It's just that some manufacturers (esp. American) persist in using 60s technology in their cars, and what's the reason for this? Are pushrod/OHV engines really much cheaper to build than more modern OHC or DOHC layouts?

Among the Big 3, only Ford is shying away from this. I think they no longer sell cars with this kind of engine.

[mbt]

what's wrong with pushrods?

pushrods work, and in certain applications, in fact, work very well (as in the corvette). there are certain advantages to pushrods, chief of which is that it allows significantly smaller engine dimensions (mainly reduced height, since there are no overhead cams).

[airshaq20]

It's just that some manufacturers (esp. American) persist in using 60s technology in their cars, and what's the reason for this? Are pushrod/OHV engines really much cheaper to build than more modern OHC or DOHC layouts?

Among the Big 3, only Ford is shying away from this. I think they no longer sell cars with this kind of engine.

You just answered your question - its the cost of building and designing the engine. FYI, it cost HUNDREDS of MILLIONS of $$$ to design, develop and build an engine so we're not just talking hundred of thousands of dollars here.

When you are into any business, you have to think about ROI too.

[mbt]

in the case of GM, i doubt it's because of financial/business reasons. they could well put a Northstar V8 into the corvette, but don't,... hehe. maybe it's a "soul" thing :D

[Karding]

in the case of GM, i doubt it's because of financial/business reasons. they could well put a Northstar V8 into the corvette, but don't,... hehe. maybe it's a "soul" thing :D

GM is so cheap to design a new one. Of course, the longer the engine stays in production, the less money they spend for re-engineering. But for crying out loud, its already a quarter of a century or maybe longer.

And then, the question of supply and demand arises...

[speedy]

Why would you throw away something that may be old school but works! Now, for example the new corvette Z06 has the same pushrod V8 configuration as previous models. But now is bored out to 7.0L ! Producing 500 hp! Its hard to find engines of that size that can produce 500+ hp. (Racing version has 600+) There are so many different ways to increase hp and performance that GM has stayed with a "proven" and "reliable" power plant. Improvements have been made in exhaust and waste management as well as intakes. The other upside to this is the fact that not all corvette fans could afford the latest and newest models. Buying older used models is very appealing because of the price and the accesability of spare parts. (since the technology has been around since the 60's) I think everyone has good points as well, shaq is right about R/D on engines and yes if they are still selling and engine they paid for in the 60's but is still selling like hot cakes, why not! The other thing is the "passion" for the cars that they are in. Corvettes have been known for having a very large following. There are a lot of die hard fans that consistently buy corvette products. I, myself am one of them. I am on my 2nd corvette and I am seriously thinking about the new Z06.

[yebo]

hilig din nila sa hemi engine design and that's why they have push rods. you can't put overhead camshafts on a hemi.

[woodfire]

For me, a HEMI ENGINE is one of the best performing muscle machine ever. Muscle & brawn!!! Old school Hemi Cuda's still can put fear and terror in the street and strip.

Nothing bad about push rods though! Design? Technology? Hey, its all relative. I'll get a push rod Hemi engine or push rod high performance engine anytime.

[yebo]

exactly! why junk something that works very well just because it's a push rod?

[squala]

I'm kinda wondering why Chevy went back to pushrods when they have already built a DOHC layout in the ZR-1. True, they may have spent a lot in research and design for the engine (reflected on the hefty ZR-1 premium over the pushrod model), but shouldn't they have just developed that further for the current car?