Non-Turbo conversion - transmission question

Hi. This may be hard to be address by the mainly US based members of this board but I'll give it a try: I am swapping a 1991 JDM Cyclone into a non-turbo 1989 4WD/4WS GTi Galant (Europe spec car). The engine is coming along with a 5 speed manual transmission and transfer case. Will the stock rear differential work with the swapped transmission? Many thanks on advance.

 

[mountaineerjeff]

I believe mounting wise it should be fine, the only problem will be to make sure you have the right/matching ratios/

 

anyone able to reflect on the ratios ? do I need a turbo rear differential or will the non-turbo diff work?

 

[donkeylips]

I know that if you have a galant gsx here in the US, and you want to run a dsm or gvr4 transmission, you need to run a dsm or gvr4 rear diff.

 

[mitsuturbo]

Or, you can swap the ring and pinion in from the front diff of the ggsx transmission.

 

[donkeylips]

But ggsx parts are hard to find, at least here, and if you break something you're screwed. Maybe they're more abundant there but the best bet is to go with the gvr4/dsm rear diff. Might as well upgrade to a 4-bolt.

 

thanks for taking the time to give some feedback. If I am to change the rear differential, would any GVR4 or DSM Turbo AWD diff fit? any known differences in ratios? anything I must be aware of when looking for parts online. Any suggestions as for where online to look for parts?

 

[mountaineerjeff]

well here we can just throw in a rear end from any vr4/dsm, but you are going to have to be careful. there are many more options available overseas and many more combination, you have multiple ratio's available in 4bolt and 3bolt, with and without lsd. the easiest way to do it would be to just get both out of the same car.

 

[Muskrat]

Get the serial number off your transmission, and refer here for the final drive ratio. Or do a Google search for it, if it's not in that list.

AFAIK there are only two possible final drive ratio's for the AWD car's. 3.909 (in NA this was in automatic DSM's, and the non-turbo awd galants) and 3.545 (NA manual DSM's and VR-4's).

I wasn't able to find the Galant GTi final drive ratio with a google search, but I'd guess it has a 3.909 rear end. It would be geared higher to give more torque w/ the naturally aspirated engine.

What you could do is attach a degree wheel to the input on your rear dif, and turn it until you get 1 full revolution on the output shaft, and note how many revolutions on the input it took. That number will be your final drive ratio for the rear dif.

 

[misterfixit]

galant gti =2.846 rear. box is a w5m31 while a vr4 is a w5m33.

rich

 

[mountaineerjeff]

so that sounds like fun for me. then could have an even nicer ratio for daily driving.

 

[misterfixit]

You will have to make sure that the ring and shaft from the w5m31 will fit in the w5m33 box.

Rich