anybody know about what the clearance is between the piston and quench area with u.s. itr pistons in a gsr motor with a single layer head gasket? i've heard that the piston will likely hit the quench area of the combustion chamber since they are blocked off on a gsr head.


[Modified by da6vtec, 9:55 PM 12/7/2001]


[Modified by da6vtec, 9:56 PM 12/7/2001]

 

They shouldnt touch. CTR piston possibly, but not ITR.

 

we shall find out tomorrow eh? wake me up early.. like before 9am foo! i gotts to wash mah R.. aight...

 

No problems. I got the US ITR pistons in my GSR, and the CTR cams work fine. Also the 402A spec cams from Crower work ok too.

 

the headgasket he is using is a stock honda gasket with two layers removed, only one left and sprayed it with copper paint thing to seal better.. now he was told by a "very" reputable mechanic in slocal that the acutal piston is hitting the quench area on the head due to the headgasket method he used.. the compression right now is estimated at 11.5 but still that shouldnt happen from my understanding.. somehow it doesnt really make sense.. the car feels great and sounds totally normal. Any ideas?

 

it shouldnt touch.
if you want to be sure, pull the head and look.

 

here 's the 411 guys. it was hitting the quench area where the sides are blocked off on the gsr head. it was so bad that the "IN" was stamped in from the piston since the lettering on the piston is raised. so now i am running a complete head gasket, clearance is good now.

this was my set up

gsr block and head
itr rods
u.s. itr piston
itr valves
itr cams
stock head gasket with two layers removed

it never made any noise and i rev'ed it to 8800 a bunch of times, but it was hitting for sure. i guess i was just lucky that it didn't blow. so let this be a lesson to all you. itr pistons+gsr head+thinner head gasket=bad!


[Modified by da6vtec, 9:04 PM 12/8/2001]

 

Was the block decked at all?

 

the block and head were never decked....the clearance was probably about 0.25 mm with the single layer head gasket....with a complete gasket it was about 0.8 mm


[Modified by da6vtec, 10:31 PM 12/8/2001]

 

Would you guys say then, that if someone where running the same set-up (B18C1 with USDM ITR pistons) with a Spoon head-gasket and milled head, 40 thou, with compression up to about 12.1:1, that he would run into the same kind of clearance problems as da6vtec?

 

Actually I'm curious to know the answer to 35Mugen's question as well.
Anyone?
SgT?

 

i'm pretty sure that set up would have a problem. my head was not even milled. your friend should pull his head off and take a look.

 

I'm going to be using a B18C1 block/head with USDM ITR pistons/rods, full head gasket and the B18C1 head is milled 30 thou. Any potential problems there and does anyone know what the CR would be?

 

would there be any clearance issues with a b18c1 and the ctr pistons and stock head gasket?

 

If this is such a problem, why do lots of people fun CTR pistons with a GSR head? I know theres a few people on this board running that setup.

 

it's fine if you run a complete head gasket. if the head is milled it should be fine. but you should check the clearance by having the motor clayed. the only area that was hitting was at the ends where the gsr head is blocked off. i think with a single layer gasket the clearance was about .25mm. with a complete gasket the clearance is 0.8mm. it's not the piston to valve clearance that your worried about. it's the piston to head clearance. that's why you can run ctr pistons in a gsr as long as you use a complete head gasket