8.1L cams???
08-25-2013, 10:00 AM
#1
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8.1L cams??? what makes the 8.1 cams unique. apparently they are not the same as other late model gen IV big blocks?????. does anyone know the the specs on the '103' cam that was recommended to me. thanx , crossy
09-09-2013, 12:50 PM
#3
the 8.1L is distributorless so i believe there is no distributor gear on it but there is an oil pump shaft that runs down the rear of the engine which i think is driven by the camshaft. And the oil pump is a traditional kind like in a SBC. And i believe you have a reluctor wheel on the cam for the cam sensor and the PCM.
for gen 4 big block stuff is that going back to the blocks that used distributors? if so then you have a gear on the cam to turn the distributor and oil pump. I know the LS1 was GEN 3 and they had gerotor oil pumps mounted on the front of the crankshaft. i don't know what generation motors had what along the years, and there aren't any "late model big blocks" really.
for gen 4 big block stuff is that going back to the blocks that used distributors? if so then you have a gear on the cam to turn the distributor and oil pump. I know the LS1 was GEN 3 and they had gerotor oil pumps mounted on the front of the crankshaft. i don't know what generation motors had what along the years, and there aren't any "late model big blocks" really.
09-10-2013, 08:49 AM
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Different firing order I believe, yes?
The cam sensor reads off of the cam sprocket of the timing set on the later 8.1s. Can't recall where the early ones read but they were unique.
The cam sensor reads off of the cam sprocket of the timing set on the later 8.1s. Can't recall where the early ones read but they were unique.
03-03-2014, 08:59 PM
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There's a different firing order in the new vortec big blocks. Additionally, you're limited by the stock iron heads / cast pistons in the engine. The 203 cam is as big as you can go before you need to replace the pistons and cut down the valve stems on the iron heads.
