piston to valve Ok??
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piston to valve Ok?? I am going to have a stock CI block with flat pistons with 2 cc of valve relief. Cam size is 231/237 .575 .575 112 +3 or 4. I want to get my dcr up a bit more by going with .040 gaskets and running a set of milled 5.3L heads.
My question is how much can I mill the heads before piston to valve becomes likely? I would guess I could mill them quite a bit considering this isnt a monster cam in duration or lift. What you guys think?
My question is how much can I mill the heads before piston to valve becomes likely? I would guess I could mill them quite a bit considering this isnt a monster cam in duration or lift. What you guys think?
The 5.3 heads have smaller valves than the 241 or 243 castings so if your worried, I'd put in LS6/LS2 valves to maximize your ptv clearance. Aftermarket valves will kill your ptv clearance. Check out this to comparison between Ferrea (.060) and stock ls2 (.020)
As for milling, I'm going to guess somewhere in the neighborhood of .015 with that cam.
Is there anyway you can measure now and get a baseline to see where you're at with the 5.3 heads?
As for milling, I'm going to guess somewhere in the neighborhood of .015 with that cam.
Is there anyway you can measure now and get a baseline to see where you're at with the 5.3 heads?
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From: Watertown, NY
Originally Posted by Xtnct00WS6
The 5.3 heads have smaller valves than the 241 or 243 castings so if your worried, I'd put in LS6/LS2 valves to maximize your ptv clearance. Aftermarket valves will kill your ptv clearance. Check out this to comparison between Ferrea (.060) and stock ls2 (.020)
As for milling, I'm going to guess somewhere in the neighborhood of .015 with that cam.
Is there anyway you can measure now and get a baseline to see where you're at with the 5.3 heads?
As for milling, I'm going to guess somewhere in the neighborhood of .015 with that cam.
Is there anyway you can measure now and get a baseline to see where you're at with the 5.3 heads?
If you haven't seen this thread yet, there is some good info here.
Predator is usually right on with head, cam and valvetrain recommendations.
On another note, since your pistons already have valve reliefs, and that cam should clear with a stock head, I can't imagine you'll have any piston to valve clearance problems unless you go to a larger diameter valve that doesn't clear the existing reliefs.
Predator is usually right on with head, cam and valvetrain recommendations.
On another note, since your pistons already have valve reliefs, and that cam should clear with a stock head, I can't imagine you'll have any piston to valve clearance problems unless you go to a larger diameter valve that doesn't clear the existing reliefs.
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From: Watertown, NY
Originally Posted by hammertime
If you haven't seen this thread yet, there is some good info here.
Predator is usually right on with head, cam and valvetrain recommendations.
On another note, since your pistons already have valve reliefs, and that cam should clear with a stock head, I can't imagine you'll have any piston to valve clearance problems unless you go to a larger diameter valve that doesn't clear the existing reliefs.
Predator is usually right on with head, cam and valvetrain recommendations.
On another note, since your pistons already have valve reliefs, and that cam should clear with a stock head, I can't imagine you'll have any piston to valve clearance problems unless you go to a larger diameter valve that doesn't clear the existing reliefs.
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From: Watertown, NY
Originally Posted by JPH
valve reliefs in the pistons, you should have plenty of clearance. most reliefs are atleast .150 deep.
Think i have room to mill the heads .030? That would get my DCR where i want it as while at the same time keeping overlap centered at TDC. Most cams come ground with 2 degrees advance already right?
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Originally Posted by brad8266
yeah the reliefs are .165 intake and .107 exhaust
Think i have room to mill the heads .030? That would get my DCR where i want it as while at the same time keeping overlap centered at TDC. Most cams come ground with 2 degrees advance already right?
Think i have room to mill the heads .030? That would get my DCR where i want it as while at the same time keeping overlap centered at TDC. Most cams come ground with 2 degrees advance already right?
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From: Watertown, NY
Originally Posted by JPH
2 to 4 degrees is standard, depending on cam manufacture.
Originally Posted by brad8266
Ok, so my 112 LSA cams ICL would be 110 if I install it dot to dot as long as it has 2 degrees ground in already?
