Diff Replacement Options

[D.I.Y. Mik]

Hi guys, my diff is on the way out, and i was wondering:

1 If anyone has ever fitted a non Skyline diff in a Skyline, and what was it, how was it done.

2 Or, What diff centres fit in what housings, which housings fit in which models (can i put a 33 diff on my 32)?

I want to fix my diff on a budget, so any useful info is appreciated.

[GTSBoy]

R32 and R33 are the same diff, but there are differences. The R32 rear mounting points are different, so you'd need to swap back plates over. The R33 diffs use bushes in teh front mountss and the R32 doesn't. So you need to obtain bushes to fit an R33 housing to an R32.

The internals are essentially the same (both crappy VLSDs, 4.11 and 4.3 ratios for manuals and autos). Aftermarket diffs sometimes use different length half shafts (like, they'll use one the same length as the Nissan diff, and another a different length to the Nissan diff).. That can be a complication if you're sourcing a centre from somewhere and it doesn't come with everything you need.

Helicals from S15s can be used. I put a 4.11 crownwheel and pinion onto an S15 helical centre and put the whole lot into my R32 housing. Cost a fortune in the end, just about could have gone for Nismo 1.5way instead. Some R34 manuals were helical, and those diffs will drop in in the same way that an R33 one will.

There are not any really useful non-Nissan internals you would put inside a Nissan housing, and there are not really any non-Nissan housings you would bother trying to put into an R32 chassis. Too much f**king around for little gain. The Nissan R200 is a pretty strong diff.

[R31Nismoid]

You have a R32, you can just rebuild the stocker and tighten it up.

Simplest solution there is.

[GTSBoy]

Except that it's not a simple solution. Shimming a viscous diff is a mug's game.

[D.I.Y. Mik]

So the easiest is take it to the diff dr,

the cheapest is a second-hand centre from 32, 33, or helical 34s.

Sounds pretty straightforward.

Thanks for complete info, everything i need to know.

[Dan_J]

cheapest option is to shim it locked with 3+ mm of shims but will need to sort out the back lash spacing shim if you want it 100% comfortable

[R31Nismoid]

Except that it's not a simple solution. Shimming a viscous diff is a mug's game.

http://www.skylinesaustralia.com/forums/topic/164288-diydiff-shimming-for-r33-gtst/page__view__findpost__p__3046095

[GTSBoy]

Ignores the fact that you're not making an LSD. You are making a metal grnding machine.

[R31Nismoid]

He did say... budget!

[Manuel Kasko]

So there seems to be the very cheap option of shimming which some think is pointless and grinds parts not meant to grind.

Then the expensive option of aftermarket for $2000+

Farken hell

[R31Nismoid]

$2000?

I had a Nismo 1.5 GT Pro in and running for $1500...

[Manuel Kasko]

I'm a poor kunt lol

$500 is the same as $2000 to me

All of its out of my reach haha

Honestly look at my DP I fight other bums for a living

[R31Nismoid]

Good ole Roofus

[boostn0199]

Weldy ftw cheap, simple and strong if done right. Once i went weldy never used anything else.

[Manuel Kasko]

Thats because you drift haha

[sydking]

assuming yours is a S2 kasko? r33s2 A LSD was factory - I have the same in my 33 GTS4, Best option ive come across is getting it shimmed to a Nismo spec.

otherwise fork out the $1500+ for a nismo

[Manuel Kasko]

S1..

[sydking]

Has anyone noticed much diffrance with getting power to the wheels with a diff such as a Nimso - Or even one shimmed to specs

Helped with traction?

The way i see it- Its a locked diff that allows both wheels to spin at the same time- Kind of defeating the purpose of the diff in the fact it was designed to allow both wheels to roate at diffrent speeds.

Just thinking from a street/circuit racing point- I can understand for drift single legger would not be as efficent and predicatble.

Edited August 30, 2012 by sydking

[GTSBoy]

Question is serious?

An open diff does what a diff is supposed to do, which is to allow you to drive around bends without the left and right wheels fighting each other because of the different wheel speeds required to cover the different length paths. An open diff will usually spin up on wheel under heavy acceleration, and is therefore useless in a performance car.

An LSD (I presume you are talking about the Nismo LSDs, and not some solid spool diff that Nismo may or may not do that I don't know about) is intended to reduce the tendency to spin up one wheel. They do not "lock". There is a maximum differential torque that they will handle before they will allow slip to occur between the two wheels, and hopefully that max torque is higher than the expected loading in the application it is installed in. If you hit them hard enough you can still make them slip relative to each other.

And yes, it is all about traction. Better 2 wheels spinning and actually providing some drive than one wheel spinning and providing none at all (in the extreme case), but at anything less than the extreme case, you get to apply acceleration up to the grip limit of the two wheels together, instead of up to the limit of whichever wheel has the lowest grip (and so would spin first).

[sydking]

Always serious mate, Cheers for that.

Just trying to work out what i should do for my gts4- as the rb26 now in im thinking il require something shimmed up to help get the power down,

Just been reading the DIY diff shimmin thread- Some good info and results in there too, I think it could be the go

Edited August 31, 2012 by sydking