Diff Dilemna! Need opinions!

I know this is a bit late, but something that was not mentioned here at all.
If you were running street tires at standard pressure, on the sticky track they will
chatter like crazy when cold. You need to drop psi and warm them up if just a little.
I ran into this with my 69 340 4 speed dart at Bandamere on a 60 deg evening. When the guy's on a test&tune night said I should run my car with them. This car NEVER wheelhopped in 28yrs of street and track with or without slicks. I dropped the tire psi to 15 and smooth as glass. That first launch chattered so violently that the glovebox emptyed. I was suprised I did'nt break everything. Another old guy like me said "did'nt drop yer tire pressure did ya!!!" Cold track/fresh rosin/ hard, over psi stock radials=bad chatter!!!
Just another tuning thought,
Rick