XFI cam and .026 head gasket... PTV issues?
#1
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Some of you know I'm going with the Comp Cams XFI cam, the 230/236 @.050 and .576/.571 gross lift (with 1.6 rockers).
I decided to raise compression a little bit with the Impala head gasket (.026 thick instead of .039 like the aluminum headed LT1 version).
Short block is stock, with the 'eyebrow' valve reliefs, and the heads are surfaced no more than 0.010. Probably more like .005 as a cleanup. (Of course, Jasper did get hold of the heads once, many miles ago...)
Anyone think I'll run into piston-to valve clearance issues? If so, anyone want to explain just how to clay the pistons, preferably in a way I won't have to buy yet another set of head gaskets after the process, since the heads are torqued down now?
Thanks for your input!
I decided to raise compression a little bit with the Impala head gasket (.026 thick instead of .039 like the aluminum headed LT1 version).
Short block is stock, with the 'eyebrow' valve reliefs, and the heads are surfaced no more than 0.010. Probably more like .005 as a cleanup. (Of course, Jasper did get hold of the heads once, many miles ago...)
Anyone think I'll run into piston-to valve clearance issues? If so, anyone want to explain just how to clay the pistons, preferably in a way I won't have to buy yet another set of head gaskets after the process, since the heads are torqued down now?
Thanks for your input!
#2
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I don't think you'll have PTV interferance, but it's best to check rather than hope. If you're going to use the clay method then the head must be removed. You can use a checking spring to measure the actual clearance between rocker arm and valve stem tip when the valve is pressed manually to touch the piston.
#3
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Gaskets are .049 stock aluminum head, .039 Felpro for aluminum, .029 stock iron head, .026 for Mr. Gasket 5716
I have yet to hear of an LT1 with PTV issues especially not on a stock shortblock.
My heads are cut .032 using a .026 gasket on a stock shortblock with a suprizingly good .022 deck height and a bit less lift than you but had no problems.
I have yet to hear of an LT1 with PTV issues especially not on a stock shortblock.
My heads are cut .032 using a .026 gasket on a stock shortblock with a suprizingly good .022 deck height and a bit less lift than you but had no problems.
#5
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i am doin the ms gasket .026 gasket, custom cm motorsport cam (.570/.569) lift, 1.6 rockers, head decked .020 to get as much compression as possible
The motor was stock rebuilt, 355 with standard valve reliefs...my intake valve is a 2"
Should I be ok?
The motor was stock rebuilt, 355 with standard valve reliefs...my intake valve is a 2"
Should I be ok?
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Originally Posted by fergymoto
My valves didn't clear the pistons with my setup (Mr Gasket 5716). Heads have been shaved .015 I think. Cam specs in sig. Stock short block. I had to cut a good bit into the valve reliefs.
what size valve are in the heads
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Originally Posted by 94z28L
would it be the duration of the cam that causes PTV issues tho or would it be the lift?