Peter
Hi Rick,
 
I would have thought that the original Transaxle in your 1997 SW20 is an E153.
Why not stay with that ? & fit the Beams to it, when you do the switcheroo.

No, my SW20 is a NA Bathurst, which i believe has a S54. I am thinking of using my existing gearbox though as i know its in good condition with no issues.

some not all beams boxes got an lsd. iirc the beams lsd will have a big sqaure edged bar when looking through the centre, unlike the open and turbo lsd boxes which have the more hex/tapered edged bar through the guts.

So, the top pic is Lsd?

Thanks Eric, I'll include it in the shortlist
Just an FYI Rick me as well as other NA owners have had their diffs kick the bucket in the high kms (150,000km +) region but yours is a lowish km yeh? Then again I did buy a lemon, first 2 tranny oil changes were pretty bad
And yeh top one is LSD, bottom pic is open diff

I also had a chat with doug (Falcon) lately, who rebuilds these gearboxes, and he was saying that the thing that kills the open center diffs in these is wheelspin, as the bearings arent designed for it and burn out (If I remember correctly)

Hopefully that gives you some more insight into why your diff kicked the bucket :)
 

That makes a lot of sense. If only someone told me earlier
Anyhow...duly noted!!

rikkir
Are you sure the Beams S54 is LSD? The one i got in the halfcut doesn't appear to be LSD. I was going to stick with my existing S54 as i know its in great condition...

Some BEAMS S54 boxes are fitted with LSD's. Many are not. The diff that came in my Celica/BEAMS half-cut wasn't, but as I didn't really want one anyway, that wasn't an issue.
 
The biggest difference between the Bathurst S54 and the Jap-spec BEAMS S54 are the gear ratios.  The BEAMS box has shorter and closer ratios, which I happen to enjoy very much. If you were doing a lot of driving over the 110kph highway speed limit, top gear might be a bit short for some, but since that's not an issue for me, I much prefer having the closer ratios.
 
My mechanic just took the entire guts out of the BEAMS box and put them in my Bathurst housing, just keeping the selector rod from the Bathurst box (as the one from the Celica box is back-to-front in an MR2 due to it being FWD).

mister2
The biggest difference between the Bathurst S54 and the Jap-spec BEAMS S54 are the gear ratios.  The BEAMS box has shorter and closer ratios, which I happen to enjoy very much. If you were doing a lot of driving over the 110kph highway speed limit, top gear might be a bit short for some, but since that's not an issue for me, I much prefer having the closer ratios.

You can also do the 5th gear swap to help drop the highway cruising revs - http://www.twobrutal.co.uk/forum/showthread.php?15160-How-to-change-S54-%28Mk2NA%29-5th-gears
 
This allows you to swap the 0.82:1 5th for a 0.73:1, dropping the revs around 800rpm.

Did some reading a while back on mr2.com and they said Gen 3 3SGE S54's some gears were shorter than Gen 2 3SGE S54s not sure of the creditability on that tho..
 
I also came across a thread about Paul Woods putting a helical LSD from the Spyder's C56/65 into a S54 so that's possibly a cheaper option for the NA guys rather then shelling out for a Quaife. Just a matter of finding someone willing to part with it hehe
 
Extended 5th gear would be dainty lol