I think it is all better now...........

Yes,winter blend was part of the problem.Likely why it toasted a piston at the track. It runs .5 leaner on winter blend and I was WAY too close to the edge as it was.
Put some 100% "pure-gas" in it{alcohol-free},made a big difference.
Also found the vacuum advance on the dist. was not doing its job. Found that it was not returning to the same base timing every time. So I might have 30* at home and 33* another time. Found it purely by chance.
I had noticed the throttle response was different at times,probably the timing variance.
So too lean and unknown timing bit me.

So next year I am going to put some race gas in it to base line track use tune-up then wean it onto pump-gas with meth/H20 injection.
So now have the dist. out of the Cuda` in it.

Idle and response is nice. Can`t get it over 180* so far.

Live and LEARN.............