early 912 4 speed gear ratios ???

Hi.....I have a 4 speed trans in my drag car......
what ring/pinion ratios are available

and what 3-4th gear ratios ?

will 901 or 914 gears interchange

the car has done 130mph and high 10 second passes with what is in it but I want to build a back-up tranny

thanks for your help......

any 901/914 gearset can be used for 3rd and 4th.there are many. 1st and 2nd are real limited. 7:31 is the only R+P.

[This message has been edited by john walker's workshop (edited 04-11-2001).]