What Compression for daily boost?

[rdeis]

High, All! I'm running a 4G24 with 1G head and 16G turbo in a daily. Goals are mild-- super fun reliable daily, not massive drag. 350-400, maybe?

The bottom end was built with high compression pistons, 10.5:1, maybe? I don't recall. At the time it seemed smart to reduce that, so I computed the headgasket thickness to bring it back down to 1G stock levels. (assuming I measures everythign correctly and did the math right... heh..)

Anyhow, the car is running well and reliably, but I noticed it's not nearly as quick off the line as my backup. Given that 2.4 is more torquey than 2.0, I'm thinking that maybe I took my CR reduction too far?

What compression ratio would you recommend for pump gas, no more than 19lbs of boost, and these sorts of goals?

 

[1990TSIAWDTALON]

If its pump gasoline, 8:1. You can always compensate for lack of compression with more boost but the 8:1 would allow you a bit more ignition timing, on gas, over a 10:1 motor.
That is my take on it.

 

[jdxnc]

These days I think 9:1 is right in the sweet spot, little more efficient but not overly picky on the tune for pump gas.

 

[1990TSIAWDTALON]

I sure don't disagree, but was being "generous" over my 7.8:1 1g stocker.