joeberentsen

I have a stock 80 GS. There is a girl down the street with an S3 GSL that has sat collecting dirt for years because the clutch is out. I want it for the LSD and disc brakes.

I'm planning on taking my autocross season a little more seriously this year (well, as seriously as a guy with a 100hp car can take autocross). Would having a GSL rear end help at all? If so, how?

I did a search and learned that it's pretty difficult to swap GSL rear ends into an S1. Would it be expensive as well?

I guess what I really want to know is what advantage an LSD equipped car would have over an open diff on an autocross course.

Rusty Shackleford

from what i know the advantage of it is so that when going into a corner the power ratio will be even distribuated throughout the corner instead of having ur power go to the inside tire slowing u down......as for install if u have a 80 and she has a 83 u will need to get a different yoke and drive shaft which shouldnt be that hard on here or cost that much.....you could probly use her stuff ie driveshaft ect... look threw for my post i had somebody went into great detail about all of it...go to serch a the top and type diff in the 1st gen section

QuagmireMan

personally i dont think it would be worth the trouble.

cheesecake

I would do it as a winter project just for fun. I wish I have LSD on my rex cause its too easy to break a tire loose. I guess it depends on how much you like working on your car and what kind of shop setup you have.

brandon davis

iTrader: (3)

do it it makes burnouts that much better plus what kind of sports car do you know of that has one tire fire?

grantmac

Yes it is worth it, I can't even compare my old GS to my GSL performance wise; two different worlds. I autocross fairly regularly and I can say that you will be able to accelerate sooner out of the corner and with much more control. Only downside is that it can also make the car oversteer out of the corner a little more, but when you get used to it your times will go down for sure. Also the rear discs have much better pedal feel and control, so swap the entire assembly instead of just the pumpkin. I wouldn't build even a stock class car without one.
Grant

RUBY7

Reading this and other threads on diffs and their ratios, Iam totally confused.

Could someone please clarify.

Series 3 cars have a different driveshaft Yes? So to install a Series 3 centre in a Series 2 car you would need change the whole rear end?

Secendly this MX5 (Miata) thing, do these diffs fit all Gen 1 Cars.

I ask cause I would like a 4.1 diff and if it can be LSD or torsen all the better

Cheers Sue

Chamele03

I am not positive on this so do not quote me, but ive been tryin to figure this out aswell, i have a S1 and would like LSD, form what i gather, the S2's have the same axles, so the easiest thing to do,(what im goin to do) is just swap the center, like i said "from what i gather (read and been told)" this will work, no brake haslle no ebrake hassle, just LSD, now if the u-joint flanges are different the S2 drive shaft should just slide in place of the S1(right?)
when i find a S2 center and try this ill let you know how it goes, but ull probably have swapped by then, or bought another car.

RUBY7

Series 1 & 2 driveshafts are the same. Series 3 is different can the Series 3 center go in the Series 1 & 2 housing?

Oh and wash you mouth out, another car Ha! There is no other car

Sue

Blake

There are two driveshafts, one with a small flange (79-82) and one with a large flange (83-85). There are two axle sizes, one small (79-83) and one large (84-85). The driveshaft thing is very minor, as you can easily swap the shafts or swap the companion flange on the diff pumpkin. Axle size is far more critical because the axle housings are totally different. The LSD side gears need to match the size of the axles, so select them based on that fact alone. The only time you would have a driveshaft flange issue is with 83 components, where the axles are small but the driveshaft flange is large. In that case, just swap the driveshaft (easier) or change the companion flange (harder). You can rebuild the LSD and swap the side gears to match the axles, but the cost is about that of just buying the right LSD so hardly anyone does it.

Chamele03

I didnt mean anything other than the fact that im poor and it takes forever for anything I want, to happen.

82SilverRX7

Traction.

In my Jeep, both my front and rear axles are locked and its for traction offroad. when one tire looses it, I still have 3 others pulling. A world of difference offroad. Onroad, I assume it would be the same as getting power to hook up for the most part on a straight-away.

I know guys that weld their spider gears together in the differential, but that's for a dedicated drag car, or dedicated offroad, as turning is scary.

MosesX605

If you want to do it, you should score the entire rear housing, brakes and hubs as well as the driveshaft. The Series 3 driveshaft should fit your transmission and the rear axle housing bolts up to the car no problem. The only two sticking points are the proportioning valve and the thread pitch on the brake lines. The S1 has coarse threaded brake lines while the '81 and up cars have fine pitch. The easiest way to overcome this is to fabricate an adaptor from a short piece of hard line. Once you have the '80 axle out of the car snip one of the ends off the original hard lines and use a flare tool to make a short brake line that has a fine pitch end and a coarse pitch end. That way you can mate the hard lines on the S3 axle with the flexible hose on the S1 car. Easy, breezy, Japaneasy. As for the prop valve, some guys like to change it. I didn't and I have no troubles with my rear brakes. The balance seems fairly neutral, there was some initial rearward bias, but I installed new discs and pads when I swapped axles. Once everything wore in a bit, the bias went away.

As for the feel of the car, it really makes a big difference. As stated, you can put power down earlier while exiting a turn, but the car does tend to understeer more during the turn because both wheels are fighting to spin at the same rate, which tends to force the car into a wider arc. Pick a good line and you will be amazed at the speeds that you can negotiate turns at now. Pick a poor line and you will plow right through the exit.

Snapshot

In a word: drum brakes suck. Have had 7s w/ both.

MosesX605

I forgot to mention that you need the e-brake cables for the disc brakes as well. They will mate up with the cable going to the handle on your car though.