the Subaru's drivetrain is setup up Longitudinally exactly like all other RWD vehicles...and the AWD Skyline GTRs...

FHI makes the Differentials that Nissan buys and sells as Nissan...The same R160 thats on the Silvia's/240SE's is the same Rear Differential on all of the Subie Platforms...R180 is the next bigger shaft size and is found in anything STi and the Silvia S15 I believe...


I would remove the transfer case, gut the center differential so that there is only an input and an output to Rear...This will make the AWD power transfer system operate 100% like a RWD power transfer system...

Now, you can remove the Front Axles and upgrade your Rear Diff to handle more power...Use the inner CV joints and Rear Differential off of a Skyline GTR or a Zchassis or if you really want to take advantage of RWD launching power, Mount a Ford 9" Differential and get crazy on the engine build...

This is the way I would go about making my Impareza RWD Quick Car...