I think you may be confusing the 7.5 marking on the distributor cam with the
amount of initial advance. The 7.5 indicates that the cam will allow 7.5
distributor degrees of centrifugal advance (which is 15 degrees at the
crank). The initial advance should be 16 degrees if you have that cam, which
will give a total of 31 degrees advance.
The "smog" cam is marked 17.5 degrees and will give 35 degrees of
centrifugal advance. With this one, you need to set the initial advance at
> Others may correct me, but with a
> NON-SMOG dizzy I think you run the
> timing about 7.5 degrees advanced. If
> you have a stock dizzy you NEED to run
> the timing at 0 degrees.