I've got a GSR block with a ITR head I"m going to be pulling out the GSR slugs and put in either usdm or jdm itr pistons The usdm will give me a cr of 10.6:1 and the jdm will give me 11.0:1 I was going to run a 70 shot of nitrous on 93 octane. Is steping up 4 tenths of a point going to be too much for the 70 shot of 93 octane?

My 3rd option would be usdm pistons with only 1 layer of my head gasket 11.0:1 cr

 

Why don't you just leave the gsr pistons in the motor and run a 100 shot

 

the block has 150,ooo miles on it. also I want some more all motor power as well. I'm going to have the cylinders honed to clean them up before I put in the ITR pistons. I just want a fresh moto. Good idea on the gsr pistons, I thought about that too.

 

Go with the 11.0:1 compression pistons and a 70hp shot of nitrous. You will be fine.

 

yousa gonna run nawz dog youll be tha 9's foe sho