The specs of the engine is a b17 with CTR pistons with a b16a/b17a head with ITR cams/ITR intake manfold and T/B. OEM JDM CTR/ITR exhaust manifold. I was thinking of switching to blox b's or skunk stg 2's cams because of the comp ratio.

I have search HT and came up with 2-3 different compression ratios. The first one was 12.19 to 1 and the other was 12.49 to 1. Which is right? Hopefully with 91 octane will not ping when tuned. Any suggestions or comments would be appreciated.

 

how high do you plan on spinning this setup?

 

8,400-8,600 rpms. Currently the rods and rod bolts are stock. Planning on arp rod bolts but will have to take it apart.

 

http://zealautowerks.com/

This calculator says compression ratio will be 12.47:1 with an oem headgasket.

 

Hopefully 12.47 to 1 is good with 91 octane gas with a good tune.