[Jay S]

With the broad power band and torque of a 455 combined with an automatic, cars work extremely well with 3.36s gears. For drag racing running a 455,, which make great average power, dropping down to a 3.73 often not offer much extra performance. 3.36s are also a decent cruising gear with a 275/60r15. I would start their, 2.73 are terrible off the line, 3.36 would really wake it up, even as is.

Our 71 T37 has a 3.36 8.2 10 bolt, just over 500HP 455, and a 4000 stall.

A friend talked to someone at Randy’s ring gear and pinion and asked about 8.2s and 8.5s. To his surprise, they told him that had not seen much difference between a 8.2 and 8.5 for strength, I think 400HP was mentioned. Next he called and asked Quick performance, they told him 400 HP for the 8.2”, and 500 HP for a similarly dress 8.5”. They both recommend running cover girdles. FWIW, I tend to agree more with Quick performance’s numbers.

Gear vendors does not make much sense to me. The cheapest, and quickest option (if you kept the 8.2) would be a 700R4 has a pretty low first gear (IRC..3.06?) That gear reduction is like running a 4.0 with a th350 in first gear, and gives you a big big overdrive to cruise with. Could drop down to a 3.55 to 3.73 also, which I would do if you went with a 8.5, and run c clip epilators. But my opinion is the 3.36 was the strongest gear set you could put in a 8.2, lower gears tend to deflect the pinion more and flex the case more. The lower the gears, the more likely you will break the 8.2.