does anybody know if an fb or fc 5 speed will bolt right in as a replacement for the stock 4 speed in my '74 REPU? I haven't spent much time looking at the transmission mounts under the truck or the mounts on the rx7 trannies. Anybody else know?

 

They bolt right to the engine but i think the driveline leangth changes and the placement of where the shifter comes through the floor. Not sure, i just run the original boxes in mine. REPUGURU will know, he will jump on here and tell you how to do it. The issue with the bottom mount is that i think the cross member has to be slotted to make that work.

CJG

 

An SA tranny ('79 5 speed) is living in my REPU and is the correct length and the shifter sticks through the hole just fine. All I needed to do was slot the crossmember and rubber mount thing at every hole and shave some aluminum from the tranny so the rubber mount thing could be repositioned further forward (if that makes any sense). I did this all in '98 so it's been a while.

If REPUGURU has done it to one of his trucks, I'm sure he'll have a better explanation.

Oh yeah, I also rewired the reverse light switch and have recently fitted an NA FC ('86) starter.

 

Jeff20B answered it. The only bolt in with out cutting the floor board RX7 tranny is the 79-80 4or5 speed. The 81-85 can be adapted without cutting with the tailshaft from a b-series tranny. All the old rib cases will go right on in but you may have to do some mods to the tranny crossmember to let the mount bolts thru. I had to cut and move the middle section back and reweld to put a 76 RX3 5 speed in an old REPU I had years ago.

 

A B series tail housing has the stickshift too far forward. Check this out http://www.geocities.com/sykumash/RotaryMG_Tranny.html

 

So I will be able to put a 79-80 5 speed in without doing any modifications except possibly slotting the cross member? I don't currently have a garage or the means to do much custom work so I want this to be as simple as possible.
I think I will start looking for a wrecking yard

thanks

 

I feel safe in saying yes. Mods will be minimal to slotting and maybe some grinding on the starter lobes where it touches the tranny.

 

My old HEAVY REPU starter fit fine in the SA tranny. At least I think it was a real REPU starter. It could have been an SA though. Either way, it was still rather heavy compared to an FB or FC like what I've currently got in there.