How to weld a diff up

[H8NSKPAUL]

I thought I would start op a new thread on how to lock the diff up for drifting as on my trackday car. This is not recomended for street use as the car will want to go in a straight line all the time and this can be tricky at high speed, also I believe it would fail the MOT. But for track or drag use...it's a must.
I began by proping the car up safely, clambered under drained the oil (watch out as it's an irritant!) and removed the diff support bracket. Then I could get at the inspection plate bolts & 5 minutes later that was off and I could see this...really good access isn't it?


I decided to make a Meccano version to fully understand how it worked and be sure of what to weld up!!! It always puzzled me as to how one wheel would lite up when going for it & how when jacked up, when you turned one wheel one way the other wheel would rotate in the opposite direction.

All became very clear and it's really simple just weld up all the four small gears that connect to each other in the centre .....don't be shy with the mig weld either....get plenty on.
Next task once it's cooled down a bit is to wash out all the spatter balls. Then I made a new paper gasket and put on with some sealer. Stuck it back together, filled with just under 2 litres of diff oil.
That's it........and these are the results.....steps out a treat!!!

Hans and Paul.

[lmrdave]

Welded Diffs will pass an MOT, well my S13 did.

Raised a few eyebrows and the tester said I was a nutcase, but there is nothing about diffs in the MOT.

[mr_turbo]

true only thing it obv does is scrub out tyres which obv will fail if tyres low thats it thou

[kms racing]

Originally Posted by lmrdave

Welded Diffs will pass an MOT, well my S13 did.

Raised a few eyebrows and the tester said I was a nutcase, but there is nothing about diffs in the MOT.

yea same with all my cars with welders in , the only thing is they cant put it on the brake rollers , so they will have to take it out for a road test with a lil gadget thingy

[PukkaSilvia]

A final picture of it welded would be good

[sideways danny]

Originally Posted by kms racing

yea same with all my cars with welders in , the only thing is they cant put it on the brake rollers , so they will have to take it out for a road test with a lil gadget thingy

yes they can, gives perfectly balanced rear brakes too

[lmrdave]

Yeah my S13's welded diff fixed me rear brakes as only one worked properly

Still the best cable hand brake I've had on a car to date though.

[ov_lozza]

I had a welded diff in my volvo and it was fine, you dont even know its there until you turn at very low speeds e.g. parking etc and you get more understeer when u nail it, but then you just clutch kick and nail it more

I think the only reason you get more tyre wear is because you wanna constant drift the bugger lol

[jonnyjapanese]

Would it not be just as good to fit an LSD then you can get the arse out and still be able to drive normally, best of both worlds. I've done a bit reading around and it seems that the S13 diff inners fit into the S12 casing ??? and that you need to fit 2 short S12 drive shafts instead of 1 long and 1 short as standard?? I am going to have a go at the conversion before the end of the year so I'll post the results. Anyone with any info would be greatly appreciated. Thanks

[s13eater]

i did the conversion, 30psi told me how to do it, its easy enough when you have the bots in front of you.