S13 Slide

JIZZ!!!! my cusco rs came in today!!!






anywho i want to install it with a new final ratio around 4.6-4.8... from what i searched the only readily available ratio is 4.3, but i found rs carries a 4.77 but its for fd and no one seems to know if the fd will fit the fc...

so anyone know where to get something lower than 4.6 or if the fd stuff will fit fc??

andrew lohaus

fd stuff will fit turo fc reearends but not na. i dont know where they sell gears taller than 4.3 but if you do, good luck and tell me where.

Mazdamark

The pinion is wrong for the FD diff gear set to fit in a FC.

The gear itself would fit, you just would need a custom pinion

S13 Slide

custom pinion as in making it longer or shorter?

theonlygreat

A new pinion would come with a new ring gear if they were aftermarket, they have to be custom made as a pair. They wouldn't be able to make a ring that works with the stock pinion on an FD, so if the size of the ring (i know the ring is the same size) and pinion are the same on the FD and TII then that kit should work for either of them. So i suggest searching for somebody that has upgraded to the FD torsen unit in their TII and ask them some questions to see if those items looked similar.