Diff options for '79 Scorpion

[79Scorp]

Hey guys,

Ive recently bough a Jap imoport sigma turbo with the G63B engine in it and im going to be popping it our '79 Scorpion. I would really like an LSD or something of the like instead of the standard single pegger which we think is in need of a rebuilt anyways.

I got in touch with a diff specialist here in Perth and he had a quick look at the diff in the scorpion. He said it has a banjo diff and he also told me they dont make LSD's for them anymore and if you can find one in good nick they still arent that strong.

So at the moment im looking at options which wont cost me more than the car is worth and without requiring an ass load of work to make fit.

What can you guys suggest?

Cheers

Tristan

[Scorpma82]

given the reputation that the lsd scorpion diffs have in our forum in regards ti their strength.........i'd get a 2nd opinion

cheapest thing for it atm

[79Scorp]

Its looking like i may have to go a different dif all together and get it cut to size which will cost a mint, i heard id be looking at around $3000 for one and thats more than the cars worth!

[Scorpma82]

get a 2nd opinion

i got a ford 9" conversion for $2200........VL Commodore BW conversion was $1900.....that was drive in/drive out...supply and fit

[79Scorp]

well i may have found a borg warner set up out of a sigma which i may be able to get an LSD fitted too and it looks like it might just bolt in to the car so fingers crossed it comes through!

i might also have to get a second opinion like you said just to be sure.

[GB_BB4C]

Ask aound before you get it at diff places.
If it's just a standard Sigma diff (which is a BW) then i don't think you can get a LSD for them and they arent very strong. The Scorpion diff is stonger.

[79Scorp]

Okay so tried using a BW out of a later model sigma, there are two reasons why i cant get an LSD for it, A) it has 23 spline axles where i would need to get 28 splines (which i was quoted $850 a pair) B) its only a 7" and if it was a 7.5" i might have been lucky.

Ive been given a commonwhore diff so im going to see how much it will cost to get it shortened to fit. not looking forward to that though...

[A112H]

You should be able to get it shortened for about $1000.
When I was looking at doing this I was quoted $400 to narrow the housing and $4-600 to shorten the axles and redrill them and the discs to 4 stud.
Have a look around for a R31 Skyline diff, they don't need to be narrowed for a Sigma and they have the same centres as VB-VR Commodores and XF-AU Falcons so there are heaps of ratios and centres are cheap. They are called a Borg Warner 78.

[Turbo047]

I've been looking myself and the Skyline R31 diff is the best option as far as I can see. I'm running a locked Scorpion rear in my Turbo at the moment and do not recommend it. It's a real pain living with it day to day. Although it does draw attention as you try to drive it around car parks, and can be exciting as you drive around large wet round-a-bouts as the boost kicks in.

I did see a guy years ago who used the internals out of a Starion LSD and put them in a Scorpion diff some how. I don't think that was easy considering he was trying to sell me the centre for 2 grand and that was over 10 years ago. But no you can't easily have an LSD in either the Scorpion or the Sigma.

The Silhouette's have a LSD standard and the same stud pattern as the Sigma's. I had the measuring tape out on one only a couple of weeks ago and by my measurements the R31 is 60mm wider than the Sigma's but that doesn't look like it would be a worry. In fact the way I see it, it would look a lot better with wheels filling the guards a lot nicer than they do standard. You'd have to jig it and redo the mounts but that doesn't look too hard. Good luck.

(On the import Sigma what ass end does it have. I have seen them with an independent rear.)

[webby]

Import Sigmas/Scorpions are basically a Starion in a Sig/Scorp bodyshell, so IRS.

R31 diff would be your best bet, or a disc brake F-series Toyota diff from a YR22 Tarago/MX62 Cressida. G-series Hilux diff is also an option, but they're 5-stud, drum brake only (IIRC) and don't have the aftermarket support that the F-series does.
The reason I mention the Tarago diff is they're flog near bulletproof, ratios are available from low 3's into low 5's, they're already 4x114.3 and aftermarket LSD centres are readily available. Not sure if it'd need shortening though.
I'd personally go with the F-series, as IMO (take note of this, this is my opinion and nothing more) you'd be better off with a new Cusco, TRD or KAAZ mechanical 1.5-way centre than a worn out old factory clutch-pack LSD.

[79Scorp]

Yeah the Sigma i took apart had IRS which i have laying around if someone wants to buy it, if no one does then she will be tossed in the bin (which seems like a waste to me )

I'm going to try and find myself a Skumline diff but i dont think thats going to be easy. What i might do is, do the engine and transmission conversion and run the stock banjo crap and sort out the diff afterwards.

[A112H]

Genuine R31 LSD's are pretty hard to come by these days, the drift wannabes have killed most of them. Best bet is grab an open wheeler out of a Pintara and swap the centre with one of these;

http://www.ebay.com.au/itm/GENUINE-BORG ... 2ebdea3e2d

Or this

http://www.ebay.com.au/itm/GENUINE-BORG ... 2ebdb29a36

The Pintara's are only 25 spline not 28 spline like the Skyline or V8 Commodore but in a 1000kg car a 25 spline will be more than strong enough.

[79Scorp]

the hard part is just going to be finding one around, i might have to try ringing around wreckers who will charge me a bit... I can alway resort to the pintara items but i would like to stick to the 28's.