Makenzie71

I'm trying to acquire an FB and am wondering if a clutch assembly form a 13b FC would work with one. If so then I can use one of my NA FC trannies, rear end, and such and look a little broader for an FB...maybe get an auto and swap em.

boosted12a

the4 clutch will fit, unless itss a 79-80 car, they had slightly smaller disks. the tranny will work with some modifications, well accualy jusy swaping of the rear housing on the tranny. the shifter location and tranny mount are different, no biggie. the rear end will not work, at all! the only thing you could use would be the lsd, but it will only fit in the 84/85 cars, and you would have to pay a few bucks for some one to set yp the rear end. hope i helped....

Gregs

Yes as long as its an 83-85 12a flywheel, i actually used a gsl-se clutch and pressure plate on my 5 speed swap along with a 83 12a flywheel

-greg

Makenzie71

ok...been confused all day so...

I can use an S4 clutch disc I'm asuming in conjuction with the 12a fly and pressure plate, or does the whole clutch assembly swap?

The S4/5 tranny will bolt up to the 12a BUT I would have to swap the rear housing on the tranny? I'm assuming you're meaning this as in "the FB drive shaft will not fit the 13b tranny.

The S4/5 rear end isn't worth trying to swap over.

This sum it up or am I still confused?

hornbm

The whole assembly swaps. With the exception of the stock flywheel. Aftermarket flywheels will work for anything 1983 on.

Gregs

im using a gsl-se tranny, cluthc, pressure plate and drive shaft on my 81 12a...

hornbm

ok my bad, You can put 1983+ parts on an earlier car if they are swapped in as an assembly. You can't do it visaversa

Actually you can but that would be on a 12a only and there would be no point. Wait, you could put it on a 13b, if you used a 79-82 aftermarket flywheel with a 13b counterweight... but that would be pointless too.


In answer to your origional question, if its an 83-85 you can swap the disc and pressure plate. You CAN swap the FC N/A tranny, but that would be pointless. The FB and the N/A FC trannys are both pretty weak, and youd have to make custom mounts for the FC tranny.

You cant swap the rear from the FC because the FC has independent rear suspension, whereas the FB has a live rear axle. Plus the IRS for the FC was a pretty ****-poor design as far as IRS goes.

boosted12a

the drive shaft will fit, but its the shifter and tranny mount that cause problems! the second gen shifter is 1 or 2 inches furtehr back that an 81-85 car. and the tranny mount in all 1st gen cars is different that 2nd gen. the tranny mount and shifter housing are all atached to the tail shaft housing. so if you swap the whole unit, it bolts right up. but if its a 79-80 car the shifter is even further forward, but you can do some trimming to make it fit.

peejay

I think you are confused.

There are two different common non-turbo clutches, 215mm and 225mm. They work with all N/A trannies. The flywheels are different. 225mm clutches been 225mm flywheels, 215mm clutches need 215mm flywheels. You cannot swap OEM flywheels from different years without having everything rebalanced since the rear counterweight is built in to the flywheel.

If you had a automatic counterweight and a lightweight flywheel, then you could swap clutches around no problem, you'd just need the appropriate flywheel size.



You can swap an FB tailhousing onto an FC N/A transmission. Then it would be a straight bolt-in swap. There'd be no point unless you want taller 1st-3rd gears and a way too tall 5th. (Or if you have a collection of parts that you *need* to make work)

Makenzie71

lol...the collection of parts is usually what I end up with...thanks guys.

peejay

Remember, 13Bs are just longer 12As. It's the same engine family, anything that bolts on to the front or rear will interchange.