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Old 07-21-2012, 10:19 PM
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this 224-234 deg cam does not like a stock timing curve.

You need to modify the distributor curve as follows.

20- to 24deg base initial timing at idle.

34 to 36deg max mechanical maxing at 2800-3200rpm.

You must shoren limit the mechanical advance curve travel stop
to around a 10-12deg mechanical advance curve to allow this.
then use 2 medium tension advance springs or 1 light 1 medium
to get the curve rate just right.

Vac advance use ported vacuum
not full manifold vacuum. Limit the vac advance to around 12deg max
Limit the vac advance travel stop. then adjsut the rate by drive testing.
8 to 12deg at hiway steady cruise.

right now the spark advance is falling off when every you put it in gear
cause the distributor is set up wrong for the cam.
replace the carb power valve 4.5" so it stays closed at idle in gear
when manifold vacuum is lowest.

This cam does not really like a stock low stall torque converter
a 3000 stall is much better. This cam like gears too.

it will idle and drive just fine once the distributor advance curve is sorted out.

You cannot fix it by just swapping advance springs.
The idle timing must not drop when you put it in gear.
20-24deg at idle.
the crane cam will need the same distributor curve modification so just fix the distributor.

Last edited by F-BIRD'88; 07-21-2012 at 10:27 PM.
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