Hello,

My '80 SA came with a 4sp manual, which was what was in it until the engine blew. I've got a replacement 12a from a later FB which came with a 5sp.

So my questions are:

1. Does anyone know how much power the 4speed can handle? I'm preparing a turbo setup and when done I want to end up with AT LEAST 220hp.

2. Do I need anything special to drop the 5speed in instead of the 4speed?

 

The tranny should hold that much ok but its used, so unless you rebuild it who knows.

The FB tranny will have the shifter in the wrong spot compared to the SA. You either have to modify the tranny or move the hole in the tunnel.

 

the 4 speed is the same as the 5 speed, it just doesn't have the 5th gear parts in it.

 

The seller told me this as well. It's an '84 5speed btw. I got confirmation from the seller.

Yeah, you're right.

How certain are you about the shifter being in the wrong spot? I've found several people who say it's basically the same thing, go ahead and drop it in. Then there's several people who say the shifter is in the wrong spot.

 

The shifter IS in the wrong spot but will work with some cutting. Not sure about the console plastic though. I'm not a fan of cutting the tunnel.

 

Shoot. Well, I'll probably end up using the 4speed again then. It's kinda novel anyways.

 

Don't take our word for it then, just use a tape measure.

 

SA trans has the shift lever a few inches forward of the FB trans.

Not only does the tunnel hole need modification; none of your interior console trim from an SA will fit the lever position of an FB trans.

 

I've replaced my interior with an FB's interior already. So my console trim doesn't fit the SA's shifter as it is :P

 

So I have to wonder why you even asked in the first place? You knew
from installing the FB interior the SA tranny would not be in the right place just by looking at the tunnel.

 

The hole for the shifter IS under the hole in the trim for the shifter on the FB interior. The SA shifter is long and angled which causes it to collide with the radio mount panel.
As the 5speed is around half of the height of the 4speed I thought it might clear fine. It's not obvious by looking. Or at least not to me, anyways.

 

If you replaced the SA dash with an FB, then your only choice is to cut rear of the tunnel.

Having all the info helps.

 

My apologies. I don't plan to keep the dash so really the important aspect in that regard is just if the shifter would line up without cutting. It seems my answer is no.
So with that I'll probably proceed with the 4 speed.