my vette has 3:55 gears, 255/60/15 tires, 427 small block with about 500 hp, the tranny thats in my car is a super t10, tranny came from a 79 Trans Am, I dont know what gears are in the tranny ,but 1st and 2nd are so close together, that i could almost start out in 3rd, I want to know what would be the best 4 speed tranny that can put into this beast, Im not ready to go to a 5 or 6 speed at thid time.So please let me know what ratios i should be looking for.

If you have a "close ratio", first gear(low) is 2:20
The wide ratio is a 2:56 low.
Sounds like you could use a wide ratio unit, with the rear gears you have. A Muncie M-20 or Borg W/R will work.
Hope this helps some.

If you're going to the trouble of swapping trannys, why not go with a 5 or 6 speed?? They're great for both speed events and cruising. If a 4 speed is your choice, go with a close ratio 2:20, M-21. I've never liked the wide ratio because of the larger 'spread' between the gears. My '68 has a M-21 and it works for drags or autocrosses. I wish it were a 6 speed though!! My '96 has a  6 speed and its 'sweet'!! 

 

My 64 has the close ration Tranny and for the life of me I do not know that the hell the original owner was drinking when he ordered a 365 HP car with a clos ratio and 3:08 highway gears....

Close ratio gears serve one purpose...to allow you to keep the engine RPM's up in the power band like when road racing.. I feel they are a waste for street use... especially with a Tall rear. !

Pulling away from a light is not easy...gota slip the clutch..BUT I do admit its fun downshifting into 3rd at 80 or so MPH and fell your A$$
get pusghed back in the seat and not have to worry about your nose hitting the windshield...

Count his "street racer" as a fan of the wide ratio gear box..

Bob G.