Sigma-galant.com

Hi all,

My GC has the standard diff and leaf spring rear in it.

What options do i have for a modified rear end?
Whats the best way about doing things?

Cheers

That depends on lots of things:
What's your budget?
What end result do you want?
How much can you do yourself?

just to mention a few

Dave...

wagon diff with GE centre is the bolt in option isnt it? i cant remember too well as i just went straight to a 9 bolt borg warner back in the day

I think you'll find that's a GE Sorpion centre?

ahh i knew somebody would have better details.. a GE scorp is still a GE though so i was half right :p

My brothers GB rally car supposedly has a Torana LSD in a wagon housing. It was told to the previous owner of the car by the builder.
The one thing I know is, Torana LSD's are damn rare and damn expensive.

I was thinking a Toyota AE86 Diff conversion might be an intelligent swap. There is plenty of options for diff centres (1.5 and 2 way LSD's) and they should be able to handle the power of a Saturn, and possibly a modded Astron?

ae86 isnt exactly a huge diff though.. and not too common. me and my mates had a ke30 bush basher we cut into a ute and put a volvo diff under, what im getting at is if youre gunna swap a different diff under there you might as well go for something that can handle the power x10

theres a bloke up this way that has a speedway sigma with a torana diff, dont know if its LSD or just welded though

all that being said ANYTHING would be an improvement over a glass galant diff

I stripped a 13B bridgeported GC Galant here a little while back. It had a 9 inch in it.
That would solve just about any power delivery problems.

haha that it would.. i guess if we knew what OP's intentions are for the car we would be in a better position to make suggestions

True that.

What I'm doing is gh sigma diff being Borg Warner then commodore or falcon LSD centre bolted in I'm not ripping the biggest skids but I do want better traction using both wheels other then welding the diff I hate welded diffs unless its in a burnout car ;)

i think youll find the commodore/falcon/skyline 9 bolt bw78 series centre wont fit in a GH bw68 series housing


(stole the pic from amgis_obrut)

Sorry people, I really should have been a bit more clear.
Its a stock gc, I've got a 4g63t that will be sliding its way in shortly, followed by the 5 speed (out of import sigma).
The car is unlic, probably going to stay that way as I will be putting a cage in it. Ill just do Targa and other club events. Its not going to take the biggest of beatings, but I'm sure the standard diff won't last too long.
I know in the Mazda scene, hilux diffs are quite common. But honestly I'd rather remove the leaf springs as well.
I've seen the 4 link kits for sale, don't know if that's a better option as well? Id really like to get coil overs in there... Budget hasn't been set ha ha (always get blown out anyway) and will do 99% of it at home with mates.

rn25 hilux diffs are a good option but getting abit hard to find these days.. for a track car/basher id find something common and commercial/agricultural.. i used to have a flat tray dual cab hiace and that had a nice 8.25" diff.. try one of those mabye? or the volvo diffs like i mentioned before are pretty indestructible and have disc brakes, theyre a good upgrade for torana's and early holdens, hold 400 to 500hp with ease

4 links are great if youve got the time and knowledge to dial them properly

What's the Volvo diff?

dana 30 out of a 240 wagon.. it was just something my mate had in his paddock, fit under the ke30 ok though

I personally suggest an r31 skyline diff. Same stud pattern, disc brakes, handbrake on disc and plenty of diff centre options, some are factory LSD.

Also when it comes to driveline bigger doesn't always necessarily mean better, particularly if you don't have enough power to make use of it. Youwill just be adding more weight and bigger drivelines require more power to make them turn

yea i used the bw78 series diff in my hatchback.. theres a fair few skylines falcons and commodores around so theyre easy to find and hold up pretty good. only problem is you cant really just whack a new centre in when one blows.. theyve got to be set up properly, shimmed etc etc

His jap 5speed will die well before a BW78 and if you build it right the first time it won't need rebuilding.

Cheers Mic

Cool, bw it is then haha, how about shortening it? That could be the costly part hey? Did you guys change the diff to leaf carrier, or modify car to coil?

Mine was shortened and was converted to leaf.. they've got a short axle and a long axle, use the short axle as the long one and cut down the long axle to use as the short one, then you've only got to cut one new set of splines and when you snap the "long" axle you don't have to modify the new one

Cool ill have to do some measuring, I've got a vn ss so can work it out that way. Unfortunately I pulled the diff out and put a vl v8 diff in so its a bit shorter (and rarer)

Scorpion/Sigma or R31 diff don't need to be shortened depending on the wheels you are running.

youd need to run a fair bit of positive offset, itd make life easier to just shorten them

Do you need anything of this turbo import I've got siggylover? Cheap cheap. Justgotta start stripping it.

if i buy that GN on gumtree that im thinking about id love the interior/electric windows, mabye even the independant rear end if it would swap over.. at the moment i dont have any vehicle at all so im limiting myself to buying engine parts that i can chuck in anything

siggyloverWA wrote:youd need to run a fair bit of positive offset, itd make life easier to just shorten them

My GC is running a stock width GH Scorpion diff with 15x8 -0 rims with 205/50 tyres.




Now I know everyone is going to say the hardtops are wider and have bigger guards, but that is crap. According to the Chrysler chassis manual the overall width of both the sedan and hardtops is 1600mm. Besides, there are plenty of rim with nice dish running a +25 offset if needed.

I don't know about sigma diff into a Galant but my bw78 out of a commodore had to be shortened to fit in my lancer

Sigma diffs are 15mm longer overall length then a galant diff that's 7.5 mm either way now that's practically nothing and the vl/r31 lsd diff centres fit the gh diffs I've been told by numerous people .

I'm not talking about a GH diff though I'm talking about a bw78 series diff out of a skyline/commodore/falcon which is ~1500mm, GH is ~1400mm and Galant is 1320mm I believe.. the bw78 has one axle 90mm(I think, its been awhile, might be 60mm) longer than the other so take 180mm off the long axle and that brings it to a pleasant width

Have any of the people that have told you a commodore centre will fit in a sigma housing actually done it? I don't mind being wrong but as you can see from the pic I posted the bw68 series centre is more than a fair bit smaller than the bw78 series centre