CMS-GT4
Active member
I wanted to start a topic on final drive upgrades. Final drives have been an inexpensive performance mod for many cars.
While it is not the easiest of mods to do to our cars, it might be a good solution for those who already plan on dropping their gearboxes for a clutch and it might be much more affordable in the long run vs having to get a huge turbo kit. Alltracs might get much more out of their ct26, ct20 or ct27 with a lower final drive. For those of us with taller than stock tires this helps bring our FD closer to stock.
Alltrac ratios
Final Drive: 4.285
1st (3.384); 2nd (1.913); 3rd (1.333); 4th (0.972) 5th (0.731)
Rev: (3.545)
RC Ratios
Final Drive: 3.933
1st (3.583); 2nd (2.045); 3rd (1.333); 4th (0.972) 5th (0.731)
Rev: (3.545)
Rally ratios
St185 Rally (1989.9/6):
Final Drive: 4.285
1st (3.230); 2nd (2.142); 3rd (1.518); 4th (1.258) 5th (0.731)
Rev: (3.545)
Here is a link to a calculator to see how the FD can effect your gears.
http://www.housemanautosport.com./ratio ... ulator.htm
Rav4 Gearbox
We have already discussed that a Rav4 gearbox is an option for a lower final drive and closer ratios. The only concern being the strength of the gearbox.
Links to threads:
http://www.alltrac.net/phpBB2/viewtopic ... light=rav4
http://www.alltrac.net/phpBB2/viewtopic ... light=rav4
http://www.alltrac.net/phpBB2/viewtopic ... light=rav4
Fensport 4.4 Final drive
I found this link that at one point the fensport y2k gt4 had a 4.4 fd.
http://www.motoraddicts.com/experts/blo ... elica99414
Spensport offers this final drive as an option in one of their gearset kits. I emailed them about getting the FD separate for the standard box.
Info from their page.
3.933 Final drive (25mph per 1000rpm, ie 200mph at 8000rpm), also available with 4.4 Final drive(22.5mph per 1000rpm, ie 180mph at 8000rpm).
http://www.fensport.co.uk/partsfiles/st205tuning.htm
However it seems like most cars that make too much power they can be better with a higher final drive.
http://www.modifiedcars.com/cars/Toyota/19345.htm
Anyhow, a lower final drive may be a good option for some of us with moderate power goals.
EDIT: Added final drive mod link for reference.
http://gtfour.supras.org.nz/428ratio.htm
While it is not the easiest of mods to do to our cars, it might be a good solution for those who already plan on dropping their gearboxes for a clutch and it might be much more affordable in the long run vs having to get a huge turbo kit. Alltracs might get much more out of their ct26, ct20 or ct27 with a lower final drive. For those of us with taller than stock tires this helps bring our FD closer to stock.
Alltrac ratios
Final Drive: 4.285
1st (3.384); 2nd (1.913); 3rd (1.333); 4th (0.972) 5th (0.731)
Rev: (3.545)
RC Ratios
Final Drive: 3.933
1st (3.583); 2nd (2.045); 3rd (1.333); 4th (0.972) 5th (0.731)
Rev: (3.545)
Rally ratios
St185 Rally (1989.9/6):
Final Drive: 4.285
1st (3.230); 2nd (2.142); 3rd (1.518); 4th (1.258) 5th (0.731)
Rev: (3.545)
Here is a link to a calculator to see how the FD can effect your gears.
http://www.housemanautosport.com./ratio ... ulator.htm
Rav4 Gearbox
We have already discussed that a Rav4 gearbox is an option for a lower final drive and closer ratios. The only concern being the strength of the gearbox.
Links to threads:
http://www.alltrac.net/phpBB2/viewtopic ... light=rav4
http://www.alltrac.net/phpBB2/viewtopic ... light=rav4
http://www.alltrac.net/phpBB2/viewtopic ... light=rav4
Fensport 4.4 Final drive
I found this link that at one point the fensport y2k gt4 had a 4.4 fd.
http://www.motoraddicts.com/experts/blo ... elica99414
Spensport offers this final drive as an option in one of their gearset kits. I emailed them about getting the FD separate for the standard box.
Info from their page.
3.933 Final drive (25mph per 1000rpm, ie 200mph at 8000rpm), also available with 4.4 Final drive(22.5mph per 1000rpm, ie 180mph at 8000rpm).
http://www.fensport.co.uk/partsfiles/st205tuning.htm
However it seems like most cars that make too much power they can be better with a higher final drive.
http://www.modifiedcars.com/cars/Toyota/19345.htm
Anyhow, a lower final drive may be a good option for some of us with moderate power goals.
EDIT: Added final drive mod link for reference.
http://gtfour.supras.org.nz/428ratio.htm