l76 non dod cam lift question
11-28-2008, 11:27 PM
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l76 non dod cam lift question i am wonderingwhat the max lift on a stock l76 engine in a g8 is? It will be a non dod cam, lifters will be replaced valley cover ect, just need to know what the max lift is.
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11-29-2008, 12:00 AM
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With the DOD Lifters gone the max lift comes back to valve spring limitations and Piston to Valve clearance issues.
Obviously if you upgrade the valve springs to say something with a .600" rating then thats one limitation gone....for cams up to .600" valve lift. You'd also want dual valve springs for some of the more aggressive ramp rate cams.
With a 6.0 you'd need to check PTV clearance with any cam, but particularly anything with duration 230 or more and above say .570" valve lift. It's the timing of valve events that matters (so you could get a .600"+ lift to work if the duration wasnt too high as well).
Here's an example on a 6.0
L92 heads unmilled
GM MLS .055 gaskets
Camshaft 224/228 .591/.600
PTV clearance .073 int.,.108" exh
(some would say .090 is as close as you want)
Obviously if you upgrade the valve springs to say something with a .600" rating then thats one limitation gone....for cams up to .600" valve lift. You'd also want dual valve springs for some of the more aggressive ramp rate cams.
With a 6.0 you'd need to check PTV clearance with any cam, but particularly anything with duration 230 or more and above say .570" valve lift. It's the timing of valve events that matters (so you could get a .600"+ lift to work if the duration wasnt too high as well).
Here's an example on a 6.0
L92 heads unmilled
GM MLS .055 gaskets
Camshaft 224/228 .591/.600
PTV clearance .073 int.,.108" exh
(some would say .090 is as close as you want)
11-29-2008, 07:42 AM
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237/242, .603"/.609 114lsa ill be doing dual valve springslifters ect but was wondering ptv clearance, the cam was in a ls1 with no problem, just did not know with the l76
11-29-2008, 09:20 AM
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It's going to be a tight fit without flycutting.
A guy on the Aussie ls1 forums fitted a 237/242 (dont know the lift) to a 6.0 with L92 heads. He didn't have the cam card and just went dot to dot......it mashed valves into pistons.
Cam supplier said it would have worked if installed on a particular ICL.
A guy on the Aussie ls1 forums fitted a 237/242 (dont know the lift) to a 6.0 with L92 heads. He didn't have the cam card and just went dot to dot......it mashed valves into pistons.
Cam supplier said it would have worked if installed on a particular ICL.
