I am wondering about piston to valve clearance.

Too lazy to clay the motor, anyone ever run big cams inside a GSR with CTR's??

Thanks in advance!

 

if you're too lazy to clay, we're too lazy to tell you.

 

If the motor wasn't inside the car already I would have never even bothered to make this thread.

Unfortunately the swap is in a car and is a daily driver, hence the reason why I made this thread.

 

Usually with pro series cams, p2v isn't really a problem per say..

its normally a v2v problem.. there have been motors running ctr pistons and have had no issues, again i ask why someone would run CTR pistons in a gsr in the first place.. but thats neither here nor there..

You shouldn't have any issues, keep a 4 degree of separation
If your using standard gears which are 1 degree = 2 crank degrees go +2 exhaust / 0 on the intake
If your using the more precision style of gearing like GE or pro series does now, you'll wanna use +4 exhaust and 0 on the intake.

 

Thanks for the input, just wanted to make sure before I put them in and do a retune.

The motor unfortunately already had the CTR's to begin with, so I am just working with the card i was dealt lol

Thanks again...

 

Not a problem.. again.. i dont think there's any p2v problems.
Make sure your running a 3layer hg.. and i'd run a step colder plugs too i 'd go to 8's, if it were me.

 

I'm using BC spec 4's with PCT Pistons in my C5 with no problems. Not my choice of pistons but I bought the car with them installed already.

 

you can clay with the engine in the ca.r wtf is wrong with you?

 

Too much stuff going on in my life to rip off the head, intake manifold, header etc ect

And I'm not about to pay someone to mess with the car lol

 

C5's have more clearance.

 

The biggest problem you are likely to experience is piston to head clearance, as the CTR pistons have a timing edge (quench pads) that extend above the block deck. This will dimenish the engine's piston to head clearance to about .025", which is insufficient. You can cure the problem by using a .036" head gasket, but on non milded head.
Check your piston to valve and valve to valve clearance prior to running the engine to insure that it's sufficient.

My recommendation: Get a new pistons. CP's, wiseco's... they are half the size of those heavy PCT and have big deep valve pockets for most extreme cams and can take much more power abuse

 

Piston to head is fine.

Everything worked out with out any issues.

 

impresstive

 

good for u!

now, more importantly...... how does it run???

u got it tuned?

 

Not tuned running the same tune that it had with ITR cams.

Runs decent, for what it is...

 

I can promise you one thing, if the valves hit each other and one or more valves drop, you will hate yourself for needing to buy a totally new engine and not take 3-4hurs of your life to check..

head on and off take you 3-4 hours to perform if you know what you are doing. and I promise you it is worth the hassle to KNOW that the valves do not hit, you will also be able to play a little around with the cams on the dyno without worrying.
Even If the valve get slightly bend by a small hit (to narrow clearence and a modest valvefloat at high rpm) you even dont know it has happened until you cruice down the road and your engine suddenly stops, pull a plug and it looks like it has been chewed by a mad "steel" piraya.

Clay you motor, be sure, dont guess, and you will feel SO MUCH BETTER!

 

I daily drive pcts with Toda C-s set at +2,0 to over 9K... it was clayed and its OK.