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71cadc10 · 01-08-2021, 11:53 AM

max valve lift really shouldn't be your concern...at max intake lift the piston is nowhere near the valve.

the Amount of Duration and the installed centerline is what you are looking at.
the earlier you open the intake the tighter it gets...most cam places can give you a fairly accurate range of duration and installed Intake CL that should clear.

think about the intake lobe, valve starts off the seat Before TDC, we often see on the cam card the degrees BTDC at the .050 lift point (5 to 15* typical numbers)

The amount its lifted at TDC and right after that is where it will be closest to the piston top.

01-08-2021, 11:53 AM	#4
71cadc10 Registered User Join Date: Apr 2004 Location: Boiling Springs, PA Posts: 435	Re: What to check before buying cam & avoid piston to valve clearance problems? max valve lift really shouldn't be your concern...at max intake lift the piston is nowhere near the valve. the Amount of Duration and the installed centerline is what you are looking at. the earlier you open the intake the tighter it gets...most cam places can give you a fairly accurate range of duration and installed Intake CL that should clear. think about the intake lobe, valve starts off the seat Before TDC, we often see on the cam card the degrees BTDC at the .050 lift point (5 to 15* typical numbers) The amount its lifted at TDC and right after that is where it will be closest to the piston top. __________________ 71 C10 long bed, 2003 6.0L, 06GTO E40, T56, 12bolt 4.10 rear