Tony, 7-8 inches sounds low to me for that combo. What is your timing setup like? Initial, total, all in by? Have you tried a lighter spring setup for the dizzy? No vacuum adavance?
Brad (my engine builder) has the total timing set around 40 degrees...don't quote me on that. Total timing is in at 4000 rpm with the heavy silver springs installed by MSD. Centrifugal advance is 21 degrees.
Haven't tried different springs yet.
No vacuum advance on the MSD dizzy that I am using.
