Some Thoughts On Slant Geometry

Its not rocket science. At 28 degrees, it would not even squeek the tires anywhere. At 34, it would move about a foot, and then start hazing them.
I held it at 34, because I was not real comfortable going beyond, and I don't want the N/A tune up to be radically different than the Nitrous one.

Did you check the timing marks, to make sure the damper hasn't slipped? I am questioning this, as I can't believe it would even crank over with that much initial timing, without kicking against the starter. Most N/A slants (key word "MOST") like a lot of initial advance (around 10-15*), and run best at less then 30* total. I will garuntee anything over 25* degrees on nitrous will break parts. My 66 Cuda 170 on nitrous runs between 15 and 20* fixed, depending on how big a shot. It has run a 12.905 at 101.65 mph at 3250 lbs.