Clay pistons to check valve clearence

[89CobraGT]

Im installing my partiot performance heads today I need to check the valve clearence first can someone give me a detailed way of claying the piston , does it need the gasket on? do u put the clay on the cylinder itself? do i just hand tighten my new head bolts? and is there anything else i need to know ? I have a b cam 1.6 rr patriot performance 185cc and a stock bottom end

 

[BlownFiveLiter]

If you have an old headgasket around, use that. You'll want to use an old one because once you compress it (unless you're using an MLS gasket), it's garbage if you remove the head. Put a very light coat of oil on top of the piston and on the valves, so the clay doesn't stick to them, then rotate the engine by hand. You'll want to tighten the head bolts to spec, as if you were putting the engine together to run it. More than likely, you'll need to open up your valve reliefs on the stock pistons. The Patriot heads use a 2.02" intake valve, and to my knowledge, the only heads you can get away with that on a stock bottom end are TFS Twisted Wedges because of their canted valve design, instead of the inline valves of most other aftermarket heads.

 

[347HO]

Tape off the perimeter of your block with blue painters tape and snug down your cylinder head without the gasket.
Add the gasket thickness to your results with the clay.
In some cases, increased valve diameter will have you cut your valve reliefs larger. Go slow and at the slightest resistance to movement, STOP and find the cause before going further.

Don't forget to make sure you have the correct pushrod length too.

I prefer installing checking springs on the valves and measure the clearance with a depth mic on the retainer, but this will not tell you your clearance between valve and valve relief.