As a rwd wrx owner/driver i guess i can help out a lil bit. And I have some questions i havent been able to find answers to too. First off the coilover setups for awd subys work just fine for a rwd suby, at least with the stock transmission (dunno how another transmission would effect weight balance). on my car I am running the Stance gr+pro ssd coilovers with 12k/10k springs front/rear and Hotchkiss comp sway bars and end links. I just messed around with my damper settings a bit. Corner entry isnt too much different, just like everything else once you go rwd its a bit more sideways
Sway bars are an area that needs a lil adjustment though. Compared to my previous set up I had to soften up the rear a notch on my rear sway bar and softened my front dampers a coupla clicks.
Asfor moving the engine back and down, that might be a lil problem for clearance, unless u are running alot closer to stock ride hight than I am. Then again I usually run my cars alot lower than most subaru owners think is sane.
The biggest problem I have run into so far is the tinly stock r160 rear diff in the wrx. It just sucks. Been looking into upgrades for that myself and so far the most reliable sounding option is a custome fabricated r200 upgrade. There have been a couple done on this site already and for everyone it seems to have been a hassle since you need to order custome axles and driveshaft. Not to mention modifying the rear subframe to get it to fit. Unfortunately I havent been able to get an answer to see how well the r180 holds up with the dss conversion axles, but I am guessing the r180 is just gonna be another grenade like the r160. at least for the abuse of drifting that is. I heard that Stephen Verdier (or however his name is spelled
) was running the r180 but never got an answer from him personally. And Gruppe S are being too secretive about their setup (ie. they dont wanna help anyone else cause they are afraid they might give away some advantage
As for the rx7 trans i have heard about as much as the op.... not much. cant find anyone who has done it or seen it done, just rumors.