How to Clay a Piston
by Gman255
Clay'n the piston to verify piston to valve clearances. It isn't all that
difficult.
Apply a small amount of modeling clay or play doe (the old school type) to
the pistons valve pockets. Assemble the top end completely, using the old
compressed head gasket, leaving out the spark plug (for no compression).
Adjust valve lash to spec. Personally, I don't install the rings on the
piston ether. Its makes clean up of clay Little easer if clay is over
applied. I also use a LITTLE Pam cooking spray on the head/valve and base
gasket to prevent sticking to the modeling clay and cylinder.
Rotate engine over by hand slowly. You will experience resistants when the
cam comes upon the valve spring presser, and when valves pushes against the
clay. Continue past it. If there is a sudden stop in movement! Dissemble and
Inspect the valve imprint in the clay. If you see contact with the piston
you with need to ether clearance the piston or sink the valves. To measure
the depth of the clay use the tale end of vernier caliper, depth gauge to
penetrate through the clay to the piston. Or any other tequnice that will be
accurate.
Cam manufactures recommend some were around .060" on the exhaust side. Check
with manufactures for clearance recommendations.
I personal haven't heard of any one reporting issues with the TB 132 kit and
aftermarket cams. Beside Socal thoughts in the big bore thread. And
Firepower354's valve collusion issues at overlap. There are a few TT members
ruining after market cams with less lift (Hot cams and Takegawa stage 1) in
the 132 kit with no problems.
Hope this helps
Good luck!
