I was about to pickup a rebuilt shorty that has a CR of 11.6:1(gsr block w/p30 pistons using gsr head) and building my motor for NA, and then thought i might still boost because its not expensive to put together my kit again(still have turbo/IC).

my question is, i would like to drop the CR into the 9s(at least below stock 10:1) because my max octaine is 91. ive seen cometic makes up to a .12" HG and according to c-speed that drops me down to 9.27:1 roughly. or use a 0.098" for a CR of about 9.74:1. are these accurate, and will i run into timing belt issues with gaskets this thick(i was thinking not).

also, i still need convincing to want to boost again, so gimme some help there too .

 

will a .067-.08" thick headgasket be a problem with timing? or is it really not something to worry about?

 

i think inline pro makes a 3mm, i know there 2mm drops a b16a/b18c1 to ~9:1, yea your gonna need cam gears to correct the timing.

 

i just read that a .012" drop in the thickness would up retard timing 2 degrees? is this true? would it be correct to say then(seems logical) that a .012" increase advances timing either the 2 degrees. so adj. cam gears seem fairly necessary if you use a thick HG.

 

Using a thicker headgasket is really not the best way to go about lowering compression. I forget the specific details, as I learned them way back when theoldone.com had forums, dunno if they still do. Anyway, it decreases quench area signifigantly along with lowering static compression. These are both good things to have in a boosted Honda. Lower compression pistons would be the best way to go about it. A thick headgasket might be an O.K. compromise, but then again, having a boosted honda is going to bring about ALOT of compromises.

Also, if you are thinking about boosting again, you know you want it. It's not even a question of if you want it, it's "HOW?"

 

anyone else have any input?