What would my rear gear theoretically change to when swapping trannys?

[keith4909]

Going from a th400 to a 200r4 or 700r4. How would my rear gear change. Couldn't find an online calculator.
Rear gear 3.07

Thank you

[T_Raven]

Are you asking how OD with your 3.07 would compare to the TH400's 3rd gear?

3rd is 1:1, so just multiply your rear ratio by the OD ratio.

200-4r: 0.67x3.07=2.06 (same as if you had the TH400 and a 2.06 rear)

700r4: 0.7x3.07=2.15

First is also deeper in both so it would be like having a deeper rear compared to the TH400's 2.48:1. You have to find the difference between the 2 first gears.

200-4r:2.74/2.48=1.1048x3.07=3.39

700r4:3.06/2/48=1.2338x3.07=3.79

[keith4909]

Are you asking how OD with your 3.07 would compare to the TH400's 3rd gear?

3rd is 1:1, so just multiply your rear ratio by the OD ratio.

200-4r: 0.67x3.07=2.06 (same as if you had the TH400 and a 2.06 rear)

700r4: 0.7x3.07=2.15

First is also deeper in both so it would be like having a deeper rear compared to the TH400's 2.48:1. You have to find the difference between the 2 first gears.

200-4r:2.74/2.48=1.1048x3.07=3.39

700r4:3.06/2/48=1.2338x3.07=3.79



thats perfect. Thank you very much