msd pro billet spring setup

[als1961]

Hello everyone i'm in the process of setting up my distributor and i was curious as to what a good spring and bushing set would be?

sbc 388 9:5.1 sportman 2 heads, rpm air gap,msd 6al, 3" exhaust, Quadrajet th400 3000 stall in a 1961 chevy truck.

[KQQL IT]

My similar 406 likes all in by 3500 36° total

[INSIDIOUS '86]

I run an 18* bushing and the second quickest curve.

[hereinmissoula]

one weakest spring and one middle spring...

depending on how much initial your cam likes ( i run about 17 initial, 18* bushing for a total 35 degrees.)

alot of people run less initial. in which case use 21 or 23?? bushing to get around 34-36 degrees total. use timing tape (appropriate for your size balancer) if you don't have aftermarket balancer. try to have all in by 3000.

[hereinmissoula]

most aftermarket heads with modern efficient combustion chamber will do with less timing. vortecs also. 32-33 is fine in most cases.

[hereinmissoula]

didn't see sportsman heads. 34-36 would be best.

[INSIDIOUS '86]

Originally Posted by hereinmissoula

didn't see sportsman heads. 34-36 would be best.

I would run as much timing as possible till it detonates then back it off

Also you may want to limit vac advance so it doesn't get to much timing under load or cruising.