Unique Motorsports

Higher static compression creates more power throughout the rpm band, but it’ll lower your maximum allowed boost before the onset of detonation. Boost is worth way more power than compression, because boost raises your compression and your total air flow at the same time. With the down side of, when you’re not on the boost, you have slightly less power.

Effective Compression Ratio = static compression ratio x (1 + boost/14.7)^1/2

For a car running 8.5:1 pistons and 18psi(~max on pump gas)

8.5 x (1 + 18/14.7)^1/2 = 12.67 ECR

If you run 9.0:1 pistons and want to maintain the same 12.67 ECR (~max on pump gas), you’ll have to lower your boost to: 14.4psi

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