When my friend was doing a burnout in my RX-7. I noticed that only one tire spun. How would I make both tires in the back spin at the same time? Would having both tires spin instead of one increase acceleration too since the one wheel is not working alone? I'm not trying to kill my car or anything because I take very good care of it.

 

you need an LSD.

you can get one from a TuboII

 

Get one from a GXL, the TurboII one will require more modification since the whole rear end is different to an na.

 

His avatar says he has an S5 GXL which had no lsd. He will either need to get an lsd out of a TII which requires lots of other changes or better yet one out of an S4 GXL.

 

Now would there be any modifications needed if I get one from an S4 GXL?

 

As far as I know it would be a direct swap.

 

Weld it up.

http://zilvia.net/f/archive-faqs/148...-approved.html

 

you shouldn't need any mods for the gxl diff. but for the T2 diff you will need a new "custom" driveshaft and T2 axle shafts.

 

For the love of god don't weld it. That is the absolute worst thing you could do to a street car. And if you used a turbo diff you will either need the whole turbo rear end an a custom driveshaft or a turbo tranny driveshaft an rear end.

 

S4 GXL direct drop in into your S5 n.a.....if you plan to do a turbo engine swap in the future then might as well jump to a S4 t2 rearend but will require a custom driveshaft to your n/a transmission. I just grinded the holes outward on my n/a shaft to bolt to my t2 rearend


Reason i say s4 t2 rear over s5 t2 is because you can rebuild them and i like the design better. (clutch type over viscious)

 

I may be mistaken but Im not sure all s4 gxls had the LSD. I know the 88 gxl my little brother has had a non-lsd rear end. The clutch type LSD from a s4 (86-88) is ideal and should have a tag on the check plug stating limited slip equipped. But you can always spin an axle and verify that both axles rotate in the same direction at the same time.