hi there to all of my fellow rotary comrades,

i have an '88 FC that has been sitting for about 4 years b'cuz the motor lost compression. i have finally gotten around to almost finish saving up some money to get it back on the road but during my reasearch i decided to go with a jdm 3rd gen or RD motor and trans swapwhich is all clear to me.

in the process of my search i came across a regular motor for the FD and a cosmo one which both have 2 rotors and twin turbos. i am not sure which one i should go with b'cus i do not know if one is better (durable) and/or faster than the other. and should i be worried that on one offers warrantied on these rotary jdm swap?

please help with explaination,
AKILEEZ_777.

 

well i would look into a s5 swap not a s6 main reason is u need to use all ur old sensors from the s4 on the motor unless ur running a standalone right out of the box. all rotarys are durable if u treat them right and do the required maintenance. so if u want to do the work u can put a s6 engine in it. personally i would go with a s5 from a 89-91 Tii. people are up and down about twin turbo and single turbo. twins are nice if they are working correctly but a single is a better long run bet.

 

Both the cosmo and fd are a very involved swap. If you search youll find alot of information. You should stay s4 unless you do alot of research and are up for the challenge.

 

not
worth
the
few
hp
gained


13B cores are all capable of the same figures, the REW just has a better stock starting point.

 

S5 has an electronic omp where as the s4 is mechanical. An ecu swap would be required i believe. Im still a newbie so double check my info. But your better off staying with the S4 for ease of install.

 

Go S5 swap, the other two motors would require a standalone ecu, custom subframe, and more and more custom.

 

I would stick with the S4 engine. It is usually cheaper, it will work with your current wiring, it has a simple mechanical OMP, and you have the option of using the stock intercooler and TII hood if you wish. The S4 block is good for 400rwhp with the bolt-on BNR Stage 4 turbo upgrade.
http://bnrsupercars.com/

See typical mods here:
http://fc3spro.com/TECH/FM2W/power.htm

Why the 13B-REW and 13B-RE are a pain:
http://fc3spro.com/TECH/SWAP/FD3S/rew.html
http://fc3spro.com/TECH/SWAP/COSMO/13b-re.html

BTW, the FD RX-7 owners with serious cars will almost always replace the twin turbos with a large single turbo, so don't overestimate the performance value of twin turbos.

 

If you end up going s5, use the s4 front cover to keep the OMP. If you want to be different, go s6 or -RE but as everyone has stated, its a bit more work and you'll absolutely need a standalone.

 

a 13bre is cakewalk compared to a 13brew swap

 

If you have to ask...

You have to do A LOT more research. Or drop your car and a big check off at a shop and let them handle it.

 

Evil Aviator provided some good links for you. There's a lot of threads about the cosmo and the s6 swap, you just have to search. The s6 is the most extensive and difficult, but the cosmo isn't that easy either. If you do it right both swaps cost a pretty penny, even if you're doing the labor on your own. That means even more time of saving money and staring at your fc while it doesn't run. Like the others I would suggest sticking with the s4 or s5 tII motor. Much, much easier to do, and you'd be able to enjoy your car that much sooner.