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Compression Ratio - Boost 101
Now with a really high compression ratio and your tuner will need to remove so much timing advance (on pump fuels, 91-93 octane) it over negates the effectiveness of the boost, in turn lowering your overall power output.
If you are running E85 though then there is a major benefit to higher compression and more boost. That is where the fun begins.
Cheers,
William Knose
Delicious Tuning