Gear ratios, GTZ - quarter mile times

I'm sure that its posted here, but I, being a nooblet, was not able to find information that suited me, using search.

I've talked to Shep before in building tran's for my Evo, and he was very helpful in that regard when I had trouble there, but noticing the very tall gearing in the GTZ 3.0 v6 auto transmission-

Is there anyone here who has built a 3.0 auto trans with different ratios?

Can it be done easily, or by anyone you know?

If I am asking stupid questions, feel free to shoot me. I am no expert when it comes to these things; I'm pretty sure that; to me...if I opened up an automatic transmission it would look like it was filled with matrix code :P

Seeing that 1st tops out at around 45mph, I was thinking that someone who knew what they were doing could build this differently.

But, like I said, I know nothing of automatic transmissions, and this is my first time into FWD driveline.

there are a number of variables that will affect your times, such as existing mods (if any), launch technique, air temp and such, for example, a fast launch on a hot day will yield (in my experence) a slow E/T but the end speed won't suffer, on the flip side, on a cool day with a slow launch can yield a faster time and an end speed around 90 mph

As for the auto box gear ratios, from my research there is no shorter first gear in the v6 auto trans that Mitsu made (the 3000gt trans doesn't count as it is a diffrent design), but there might be a way of shortining up second gear (tops out at 80ish mph), the guts of a 2004+ Endevour 3.8 awd auto trans has slightly different ratios, first and third are the same, but second is shorter and fourths is taller, but as of now, nobody has done a gut swap (switch gears, shafts, planetaries ect) on an auto trans, so this might not work. Another part that would improve your acceleration (off the line in particular) would be a high stall converter (brake torquing can reach higher rpm's and this yields faster launches and the car can get on the power faster), I can't quite remember the manufactor that makes them, but they come in two variaties, a 3500 rpm stall good for 300whp and a 4500 rpm stall good for 450 whp.

if you want better acceleration, it would be much easier to swap in a 5 speed manual from an Eclipse, with this, the standard GT 5 speed has longer gearing and the GTS 5 speed has shorter gearing

+1 on going 5 speed. Don't waste your time dealing with the auto thing. Also, GTS gearing is LONGER with shorter final, GT is SHORTER with longer final.

Here you have the gear ratios for all manual 3G transmissions (from the service manual)


F5M42-2-F6ND (4G64 models)

1st 3.583
2nd 1.947
3rd 1.379
4th 1.030
5th 0.767
Reverse 3.363
Final gear ratio (Differential gear ratio) 3.722
Speedometer gear ratio 29/36

F5M51-F5N2 (6G72 GT models)

1st 3.333
2nd 2.105
3rd 1.407
4th 1.031
5th 0.761
Reverse 3.416
Final gear ratio (Differential gear ratio) 3.736
Speedometer gear ratio 28/36

F5M51-S5N (6G72 GTS models)

1st 2.928
2nd 1.950
3rd 1.407
4th 1.031
5th 0.720
Reverse 3.416
Final gear ratio (Differential gear ratio) 4.111
Speedometer gear ratio 28/36

NOTE: F5M41 gearing is not interchangeable with F5M51.

GTS gear ratios are the same as the Evo W5M51 transmission.

The shortest combination is GT gearing with GTS final, which results in faster acceleration.

I hope this to be useful for all!

Thank you both for taking the time to reply with that level of quality. It is really appreciated. :)

is it true that the gts 5th gear is compatible with the F5M42

Dont forget about final drive ratio either. The GTS is 4.111 and the EVO is 4.529. The final drive set (output shaft and diff ring gear) are not interchangeable between the GTS and EVO trans because the ring gear is a totally different diameter.

As far as auto stuff goes, i'd imagine none of the auto stuff would be interchangeable with the manual tranny, i've never tried, but I cant image any of it is the same.