Originally Posted by
Fast355
I am attaching the advance curve in the 5.7 Marine module. The distributor times at 8*BTDC and all values in the table are without the 8* base added to them. So basically add 8* across the board. As for vacuum advance, a good high performance advance curve mimics the old delco vacuum advance on the L79 327, LT1 350 and L82 350. 10* @ 10 in/hg with 0* until 5 in/hg. Should work out a bit better. At WOT you would get
23* @ 1,000 rpm,
24.5 @ 1,500,
26.5 @ 2,000,
28.5 @ 2,500
30* by 2,800 rpm.
At idle the timing would be 30.5 @ 750 rpm.
2,000 rpm cruise 36.5
3,000 rpm cruise would give 40* advance.
That should get you fairly close, then make slow changes from there. The advance curve on my L31 Express van was very similar to what I said above. With the CNP 5.3 coils I ran up to 48-50* timing at cruise though for best fuel economy and throttle response.
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