When I did the motor in my '68 I decided to upgrade to the factory electronic ignition. Years ago I remember reading that EI was light years ahead of points and good up to at least 6000rpm because of the increased coil saturation time. So this is the way I decided to go. I got a new ignition unit with the blue strain releif. I also got a new factory distributor. The motor ran fine right up to 6500rpm with no misses. So I thought all was good, but... All was not. When I would try and set the timing it would bounce all over the place starting at about 4000rpm and then retard about 4*. Trying to set the timing was a bear. I was thinking my TC was bad (though brand new) or the distributor and causing my problem.

This winter I went to an MSD set up so I would have a rev limiter and because I put on NOS. When I did this I eliminated the factory ignition box (I could have fired the MSD from the ignition box). Problem gone! The timing is rock solid right up to 5500 RPM (that's as high as I reved it with my head under the hood). I consider this a lesson learned. I think I saw someone posting about their timing jumping around, so I thought this info may be helpfull.