.020 or .030 mill with 862 heads?
#1
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Hey guys, just looking for advice on how far to mill the 862’s for my SBE LS6 with a TSP 228 cam. Will be using stock .051 gaskets but looking for as much compression as I can get with safe PTV clearance. Will be putting 2.00” valves in as well. Engine is on holley terminator X and E85, 05 CTS V, street car with mild manners. I haven’t seen too much info about 862’s on LS1/6’s while searching
Derek
Derek
#3
11 Second Club
iTrader: (3)
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What he's getting at is that if you knew the current P-V then you'd have a good idea of just how much you can mill or how thin of a head gasket you can get away with for compression.
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WE TODD DID (03-22-2021)
#4
Launching!
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I would CC the chambers to see where you are at now. I have seen them as large as 65cc. Use an online Compression ratio calculator to plan out what your CR will be. I wouldn't cut them more than .030.
#5
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I was kinda hoping for a round about estimate from someone. Still have stock 243’s on it. Not much info out there for 862’s on an ls1. Reason I’m doing it is just because I have the heads laying around, I trying my hand at porting and the car doesn’t have to be down for more than a few hours