At the Pure Stock Drags we usually have several A-body cars from 64-74 at each race, every car responds differently, some need hop-stop bars (which we recommend on all A-body's with both trans types since they apply downforce leverage proportional to the power applied, so always more pressure on the tire patch), some don't. My TH400 RAIV '70 Judge runs 12.80's with it's factory original (old!) suspension. Dan's '71 TH400 455HO T-37 needs Hop-stop bars and old front shocks (loose) to get it to hook (12.50's). I'll be racing my 'new' '70 Tempest 330 hp 400 with a TH400/3.42's this May at the F.A.S.T. race and it has an original rear suspension without the hop-stop bars. It shouldn't need them as the previous owner raced it with a 461 making 475 HP/550 TQ and he ran high 11's without wheel-hop but on 275R60/15 drag radials. We have found over the 30 years of doing the pure stock drags that the repop Firestone and Goodyear fiberglass belted bias ply tires hook pretty good with 35-40 lbs of pressure. We let the 64-66 A-body's run them as well in black wall, red or white line (no raised white letter to maintain the factory look).
Obviously, a rear suspension with new rubber bushings (or poly if you want) with good 50/50 shocks and the rear sitting at the stock (low) height with G70x14 repop tires should work well. You can also add spacers (washers) under the front sway bar brackets, install old worn shocks or 90/10's up front and install A-arm bushings without the serrations to improve lift at launch. Try bouncing your front end at the bumper...if it's stiff and doesn't move much, that is limiting the cars ability to transfer weight at launch. If it moves quite a bit both up and down, that will help on the track (not on the road).
At our event, we have the track prepped for street tires, so it is 'glued' the first 1/8 mile and the sticky stuff reapplied at the line every hour and between rounds on race day. We don't use the burn-out box, so no water ever for treaded tire, and as Boss said, drive around it not through it so you don't have water in the front tire treads to drop on the track at the line.
I hope this helps. Dennis
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