Clearance concerns

[Rumblefrog]

I recently purchased a new short block 5.0, from Ford Racing, to replace the worn-out engine in my '89 GT. I also purchased AFR 165 heads (pedestal type), an E303 cam and a set of Ford Racing M-6564-A50 1.7 ratio roller rockers.

I am not terribly experienced in the area of engine building to I am calling upon the combined wisdom and experience of the forum to allay or confirm my fears.

My question is this: with the combination of AFR 165 Heads, E303 cam and 1.7 rockers, should I be concerned about valve to piston clearance?

How do I check this?

Thanks for the help.

[84gt347]

yes, i would definatly do the clay test on the valve reliefs. pull the head off and oil the top of a piston real good. press a piece of modeling clay on to the valve relief, let some of the clay hang on to the part of the piston that is not relieved also. oil the top of the clay. reinstall the head. (use on of your old head gaskets to mock this up) set your rockers up. roll the motor over by hand. pull the head back off. measure the thickness of the squished clay with dial calipers. Hopefully someone will chime in with the acceptable thickness of the squish. i dont know it off hand