I'd like some advice on this. Was searching for this info, but wasn't able to find speficically what I was looking for.

I understand that the gear ratio on a GSL-SE manual tranny is tooled for higher acceleration but lower top speed, where an FC n/a manual tranny (specifically a GTU) is tooled for higher top speed but lower accel. Here are my questions:

1. How inter-compatible are these 2 trannys, meaning, is it possible to take the final gear from a GTU tranny (higher speed) and put it into a GSL-SE tranny?
2. Can I bolt on an FC manual tranny to a GSL-SE?
3. How many different gear ratio setups are there for the GSL-SE and also the FC3S?

Also, if you have any advice regarding tranny shops in the socal or Phoenix area, that would be a bonus. My GSL-SE's tranny recently died after getting a new clutch, and I'm friggin bummed out!! I've always fantasized about having the best of both worlds (high accel with a top speed final gear), so maybe now's the time to have my dreams realized. :p

Thanks folks.

 

Make sure you choose to only search the first gen forum then type something like "FC Tranny swap"

https://www.rx7club.com/forum/showth...FC+tranny+swap

Now aside from that topic the only thing I can say is your 5th gear will become nearly useless as it is entirely too long coupled with the GSL-SE rear gears....I generally cruise at 60 in 4th because if I need to pass anyone I dont need to downshift, 5th gear will only really serve you well if your cruising on flat ground above 60 or you always cruise at 70+...atleast in my experience that is, other than that its a great set of gears.

 

Right. The reason I want the long gear in my GSL-SE is because I drive to AZ from CA and back a LOT in that car, and I wanted the GTU 5th gear for gas milage. My mentality is, use 1-4 to tear ***, and 5th for the long drives. What do you think about that?

And thanks for the link.

 

Simple, pull the tailshaft off the gslse tranny and put it on the s5 tranny and bolt it in. You will reduce your highway cruise rpm by 500.

 

If anybody wants to sell him the whole thing all set up, I just released his WTB ad...

Private Classified ad...

 

So are you saying the s5 tranny has the same 1-4 gears that the original GSL-SE tranny has? Cuz I definitely wanna keep the 1-4 pep.

 

84-85 13b GSLSE-----3.622 2.186 1.419 1.00 .807
1986 RX7 N/a---------3.475 2.002 1.366 1.00 .711
87-88 RX7 N/a--------3.475 2.002 1.366 1.00 .697


There ya go. all the gears are slightly longer accept for the obligatory fourth gear but I've only driven a GSL-SE with FC gears and to me first gear is pretty damn short so I can't quite imagine what the stock 1st is like. as for tearing *** 1-4 you should be pleasently happy with the gearing and the speed though I can say I've never really gotten fast enough to put 4th to a real good use but third makes for a jolly good noise maker on the highway, IIRC [havent drivin mah baby in a month] 60mph lends you about 5,500-6,000 revs in 3rd and will get you to about 85 before your buring the tach.

 

What is your RPMs in 5th at 70? I am looking to go for a 2nd gen transmission sometime, but with 4.44's in the back to retain some 5th gear passing power. I do not have the 13b so torque would be an issue

 

I took care of the GSL-SE. Bought a rebuild with the stock gears. But at the same time , I just bought a rebuilt race tranny that was too good to pass up. 1st & 5th gear are from a 93 FD, and 2, 3 and 4 are from a 2000 Spirit R...all in an S4 case, 700 miles. It's a bit overkill probaly for both my cars (the other is a street ported 88 GTU, RB straight-through & HKS catbacks, no emmissions), but I guess its going into that car. Slightly out of jurisdiction, but you mind throwin down the info on that Frankenbox, Darren? :p