Dennis wrote:
> Pushrod motors don't make the same power as OHC motors of the same
> displacement, even when supercharged/turbocharged like they would in STU.
Well, I have to take a little exception with this. As the owner of a C5
corvette (well,
OK, the owner of two C5s) with an LS1 (pushrod) engine, I'm a little biased. GM
decided they would develop a brand new engine for the C5 and, after a little
discussion, they decided to develop a pushrod engine. The engineers created
heads that are a work of art - the intake creates great swirl and tumble for the
charge, the fuel injectors are positioned as to fire straight down into the
combustion
chamber, the exhaust ports are evenly spaced instead of the traditional ram's
horn
design. All in all, it's a beautiful design. It makes 345 HP and the GM
powertrain
lead engineer said they did that with a very mild cam. The current rumormill
says
a 400+ HP LS1 is in the works - if they can just make it emissions legal. 400+
HP
would put it right at the DOHC LT5 (Corvette ZR1) engine. Sure, you can't rev a
pushrod engine as high as you can an OHC engine, but for autocross, low end
torque is really more important and pushrods are quite capable of making very
good low end torque.
OK, I've got that off my chest, I feel much better.
John "Please give to the pushrod defense fund" Engstrom
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