Help With Valve Clearence

[cuong nguyen]

hey guys i had a overheating issue with my 33 gtst. it caused my head to crack. i originally thought it was my head gasket. the car was built by previous owner. so i dont know all about it. ive by told by a few ppl on here that im running a forged piston, i was also told it was 40 thou over sized too. ive added a pic of my piston so u can check it out. i pulled my head off and found out i was running a mls gasket. so i didnt blow that as i assumed first. ive chosen to go back to the standard hg but realised that my pistons stuck out a tiny bit when the motor was at TDC. i looked at my mls gasket and realised that it was like 4 or 5 layered so its pretty thick.

anyways.

my question is when i put a breaker bar on my crank bolt to see if it all rotates freely i kind of feels like that pistons are tapping the valves or hitting the head. ive got a second hand head and had it cleaned up, so its not the same head.

was my old head gasket that thick for clearance or what?

ill take photos of my old hg and measure it so u guy can see. any help would be good. originally when i bought the car the guy told me its a 2.7L stroker but i assumed he was full of it.

cheers cuong.

[89CAL]

Measure piston height at TDC, align the cam gears with the marks on the backing plate (TDC head alignment) then you shouls be able to measure how far your valves stick out at TDC. Work out the clearance from valve to piston then buy head gasket to suit

[cuong nguyen]

[cuong nguyen]

[Ben C34]

Head gasket thickness is crucial on a built engine especially with a positive deck height. I wouldn't have put a thinner one on but I don't think that would actually cause the valves to hit. Have you triple checked the cam timing?

[zebra]

They looked like acl slugs from the part number stamped on them. so they drop comp. Vlave clearance isnt going to be an issue

[cuong nguyen]

Ill triple check my timing. Should I be turning my crank or cams? To match them up

[GTSBoy]

Should I be turning my crank or cams? To match them up

Yes.

[cuong nguyen]

Yes.

Yes? Crank or cams? Which one?

[zebra]

only the exhaust cam

[GTSBoy]

I meant both. In that you have to turn the crank to TDC before trying to time the cams.

[hy_rpm]

With any interference engine you should never turn cam and crank separately fully

That's asking for bent valves

Have cams out first allign crank to tdc then install cams to tdc and attach timing belt or you can

Have the crank just before tdc 20 so all the pistons are slightly down and then rotate the cams to tdc and then bring the crank to tdc and attach belt

If you have the crank just before tdc 20 you can rotated the cams all you like and it won't touch the pistons

[cuong nguyen]

Ok I'll give it a try and see how I go. Anymore info will help out keep it coming guys.

Cheers