I think that the following should be taken into account when
installing your pistons. If memory serves, the piston in the
smallblock should have a nominal clearance from the top of the piston
to the block surface of .015 with a minimum of .0015 after deck
machining. Most head gaskets have a compressed thickness of .040-.
042. This give enough clearance. Steel connecting rods do not
stretch .030; if they do something is VERY wrong. I have used a 302
block with the 302 crank and 289 HiPo rods in an engine with 351W
heads. The engine regularly turned 7500 RPM. HOWEVER it had dead
soft solid copper head gaskets of .081 compressed thickness. In
short, many changes can be made without effecting reliability. Let's
go to heads.........The above engine has the Twisted Wedge alloy
heads with 2.02 intakes and 1.6 exhaust valves. The cam is now been
changed to a less radical Comp Cams 280H (it's now the motor in my
Tiger for the street). There is enough clearance using forged flat-
top pistons. I hope this helps in the debate. Ray
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