What compression would my GSR block have if it was stock with the only compression mods being the JDM ITR pistons?

 

11.3:1

if you want to look up different compression scenarios go here http://www.c-speedracing.com/howto/c.../compcalc.html

 

b16a pistons should yield similar compression and should be a lot cheaper

 

are you sure? i thought the ITR/CTR pistons were pretty much identical in compression...but haven't heard anything about the usdm b16a pistons...do you know the compression numbers on those?

 

nope, domes of CTR pistons rise a lot higher than ITRs, CTR pistons yield like 12.0 comp in a b18c block

 

nice...how about the b16a pistons?

 

the US b16a pistons in a B18C1 make 11.4:1 CR

JDM B16A pistons in a B18C1 make 11.6:1

 

whats a safe cr to run with 91 octane gas? i hate CA, we get cruddy gas. you east coasters and your 93 make me sick.

 

You can run up to around 12:1 compression on 91 octane.

 

While we're on the subject of JDM pistons, I just need to confirm that none of the wrist pins from the P73-00, P30, or PR3 pistons don't need any modification to fit the GS-R rods.

 

I'm running JDM ITR pistons in my b18c1, I'm pretty sure sure I was getting a little bit of knock at low RPM's (sub-3000) in 3rd, 4th, and 5th with 89. Any way on 91 it's been good. I'm running 16 degrees igniton timing.

 

You shouldn't be running 89 to begin with.

 

hi guys i need to raise the compression and i'd rather replace the pistons, than mill the head for my car has 100k+ on it so its about time for a rebuild, my question is and please answer from honest experince: what is the highest i can go that will not kill the life of my motor? i drive my car a lot and i want it to last a while? i'm running ITR cams, what do you think? thanks

 

100k? your engine is just getting broken in, you can't rebuild it now.

 

ehh? you think so. i thought that was high mileage its got 110thousand miles

 

Why not if it doesn't knock, my mechanic said it was probably the tranny jittering, I'm just paranoid My friend runs 89 on his crvtec everytime, his head is milled too. His runs great!

 

my compression is stock on my gsr and i run 91. The book says for hard condictions to run 91.. so i run 91 allways. It's not that much more... If you can afford aftermarket parts i think you should at least be able to afford 91 oc fuel.

 

amen.