In the process of assembling 11:1 pistons in a B16, stock stroke.

Is there a relationship between compression ratio and ignition timing? As compression goes up, does timing need to go down? Go up? Or no change?

Just wanting to be in ball-park for street tuning. Dyno time is expensive around here, so the closer I can get it on the street, the better.

I'm a beginning tuner, self-teaching, have already tuned afr for 10.4:1 on the street, ran 8psi. Looking to continue to run 8psi, just have more off-boost power for my daily driver. All input is appreciated!

 

Higher compression speeds up combustion so less advance is needed to put the BMEP on the piston top at the correct angle of attack (14-18 ATDC).

 

Also no need to run below 11:1 afr.

 

I agree. What I wrote wasn't clear; Motor was afr tuned at 10.4:1 compression on the street. I mean, I didn't tune timing, used boost retard 1deg per lb of boost. Afrs were around 11.5 wot. Stock JDM B16.

 

Is the correct angle of attack calculated from anything? Thanks for the answer, learned about BMEP.

 

It happens to be like that and varies slightly from engine to engine internal configurations.