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Max Sluiter
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Join Date: Mar 2006
Location: So Cal
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Originally Posted by copbait73 View Post
Neat project, I'm old school with turbos. Raising static compression ratio is the last thing you want to do, especially if you are on an engine budget.
No, static compression vs. boost is not the same. A lower static compression ratio with increased boost will stuff more charge in the cylinders thus make more power than a higher compression ratio and lower boost configuration. Leave your C.R. as is, increase the boost and spend money on a water/methanol system. Old school GT's usually made you keep the engine in a power band.
I'd paint two decklids; one ducktail, one clean.
I have been wrong before, but I do not see how the two are different. You take the intake pressure and then compress it by a certain amount in the cylinder in order to get the final pressure just before compression. Squeezing air is squeezing air.

If you fill the cylinder with 1 atmosphere of pressure and compress it to 1/12 the volume, isn't that 12 atmospheres, same as having 2 atmosphers of charge and compressing it to 1/6 the volume? Or does the temperature rise more in the turbo, meaning that there is less air mass for the same pressure?

Larger expansion ratios (the reverse of compression ratio) are more efficient. Porsche used higher static compression ratios with the water cooled head cars along with reduced boost for better throttle response and better engine longevity with the same power, or else upped the boost for more power and similar longevity.
1971 chassis, 2.7RS spec MFI engine, suspension mods, lightened

Suspension by Rebel Racing, Serviced by TLG Auto, Brakes by PMB Performance
Old 07-14-2011, 10:44 AM
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