The 002 and 003 SS spring would be correct for nostalga type drag racing. They are designed to transfer the weight on launch onto the rear - especially right rear. On launch, the rear body will rise a little and the front a little more. They will need to be used something like 9" slicks and put the snubber up against the floor. /6 t-bars, 90/10 front shocks will also help and all period correct.
For stock replacement, the factory parts and shop books listed different springs for different combos. Something like this:
1969 A-body leaf springs 6 170 3004 580
6 225 3004 581
6 225 B-HT 3004 582
6 225 B-FB,C 3004 585
8 273 Val, Da 3004 583
8 318/340 V,L 3004 584 new
8 318/340 B 3004 588 new
8 383 B,L 2808 677
HD ex. 383 2808 532
HD 383 2808 678
Leaf packs varied from as few as 4 leaves to as many as 6 on both sides.
Stengel Bros carries a good selection (made by Stanley in the US) and you can drill down to see the specs of the ones they repop. However, if you're buying them and expect them to be visually correct, find out if the interleaves and clamps are different style than original. So for most correct looking, the clamps might have to be changed out.
http://www.stengelbros.net/Plymouth-Leaf-Springs_c_226.htmlhttp://www.stengelbros.net/Dodge-Passenger-Car-Leaf-Springs_c_194.html
