A friend of mine has a '95 GSR with Jun cams. He just ordered some CTR pistons, and he was curious if there would be enough valve clearance, or if there would be any other problems with this setup. Does anyone have any information that can give me about this. thanx in advance.

 

I wanted CTR cams in my stock GSR motor and i was wondering about it too. The compression is really high like 12.4 or something, not sure. MAybe too much for street use??

 

12.4 ??? I thought they were 12.2:1.... ick.... I have a set of CTRs and have heard of others running them... but aftermarket cams.... I dunno... but would like to see it run..

 

yeah would be about 12.4:1.. It's a bit high for the street, at least with 91 octane in CA!!! I would also recommend running a blockguard! In fact, I wouldn't run any high compression pistons w/o it, it's too cheap of a part to risk cracking your cyliner wall! Why don't you run a JDM ITR piston or even a set of P30, which you can pick up at any Honda dealer. Make sure you run oversize, for that extra displacement.

you can use this compression calculator, it's reall goodcheck it at http://www.c-speedracing.com/howto/c.../compcalc.html

 

I am running CTR pistons with JUN 3 camswhich have 12 mm lift. The compression is only about 12:1 You can calculate it here http://www.c-speedracing.com/howto/c.../compcalc.html

I am putting down over two hundred horsies to the wheels with no problems. You can see my setup by clicking the link in my signature

 

Oh, my. Your car is... how can I say... gorgeous

oh yea... lets talk about your driving habits. how often do you "get on it"
how many miles do you have on this build?


[Modified by MikeSarr_GSR, 4:26 AM 8/14/2002]

 

Thanks.....
I have about 5000 km (about 3000 miles) on this build. I get on it every chance that I get taking it all the way to 9200. The Hondata has been tuned specifically for my car for about 700 km now, with my final cam gear settings at +2, 0. The head and the block have not been milled, so there is adequate clearance for the CTR pistons and Jun 3's.

If you are unsure, just have you motor builder clay the motor.

 

You got 12:1 with the unmilled GSR head ? What is the CR on these pistons in a B16B stock ?

 

Run the calculation, you will see that it is 12.042........


[Modified by canuck-mx6, 6:34 PM 8/14/2002]

 

B16A head should yield 12.0 and gsr head should yield 12.2-12.3

B16B makes 10.8

 

As long as the Head isn't milled more than 20 thousandths or thin head gasket, he shouldn't have a clearance issues......just make sure that is is tuned correctly.....

nick

 

I hate to nit-pick, but if you run the calulation, you'll see it is 12.40. You won't have clearence problems, if the head isn't milled. Even with big cams like the JUN 3s or the SKunk2 StageII.