looking into front diff

Jon9985 · **Posted:** Tue Apr 15, 2014 9:28 am

Im looking into purchasing a decent diff for the front as need to do clutch and thought might as well do both.

Anyone know where to get one? Idealy want a quaife.

Sirius · **Posted:** Tue Apr 15, 2014 10:34 am

As far as I know there are none available off the shelf, there is a TRD item but it is rarer than the proverbial rocking horse....

Some folks on here did look into having a run done but the cost was significant - over £3k if I remember rightly.

TrackToyFour · **Posted:** Tue Apr 15, 2014 1:42 pm

Unless you have a problem with the front diff I'd leave it alone. According to Dave, the new owner of the Fensport GT4X, Adrian managed to destroy his TRD front LSD and replaced it with an OEM open diff. The OEM seems to be OK upt to 500hp and related torque. I did speak to Gripper and M Factory about designing a front LSD but as Mike says, it wasn't cheap. Gripper required me to send them a stripped and clean front diff casing. I think they were going to evaluate if their stock LSD clutch pack could be accomodated.

In the end I didn't proceed as my main priority is to focus on getting the track car running. If you do decide to go ahead pleass keep us posted as I'd definitely be interested.

TrackToyFour · **Posted:** Tue Apr 15, 2014 1:47 pm

P.S. I didn't speak to Quaife as their usual modus operandii is to get the first customer to pay for all the R&D work where they don't have an off-the-shelf product. No guarantee that their product is fit for purpose. :?:

Jon9985 · **Posted:** Tue Apr 15, 2014 11:14 pm

Well thats all a bit pants then. I want a lsd in front to bring front end in on auto solo events as on tarmac the front always pushes out and i struggle getting car around a piroette.

TrackToyFour · **Posted:** Wed Apr 16, 2014 1:13 am

You can reduce the push if you reduce the roll by fitting uprated ARB's and higher rate springs. Can't remember what your spec is currently but mine was much better with TRD springs on KYB dampers and a Whiteline ARB. For events I bolt on spare wheels fitted with stiffer sidewall cut slick Yokohama A048's. These effectively increase the spring rate too and make the car a bit better round the tight and twisty stuff

Jon9985 · **Posted:** Wed Apr 16, 2014 10:35 am

Im running whilelines arbs and polybushed everything.
Currently on kyb shocks with eibach springs but aware i need to upgrade these just not sure what to go for.

Didnt think about tyres. I change wheels to 16s when in competition but tyres are basicly whatever i can find 2nd hand due to munching through them once wheels are spinning.

cms-gt4 · **Posted:** Wed Apr 16, 2014 3:14 pm

There is claims there exists one already. Sadly its no longer in my budget at this time. You may want to look into it. The advantage of the front lsd in our cars is to combat inside wheelspin largely on corner exit.
http://www.alltrac.net/phpBB2/viewtopic ... 43&t=48383

If you are wanting turn in, you may need to adjust your front caster and consider a more aggressive clutch type rear lsd as well. We are in the process of getting more 185 parts developed. The main being caster plates and extended ball joints. I am hoping to report back on these come next month.

darrylp · **Posted:** Wed Apr 16, 2014 6:20 pm

Changing the vicious coupling to give more rear bias will help as well.

--
Darryl

cms-gt4 · **Posted:** Wed Apr 16, 2014 6:23 pm

There is currently a center viscous fluid upgrade option.

TrackToyFour · **Posted:** Wed Apr 16, 2014 11:29 pm

Darryl - Don't know how you'd be able to change the torque split on the centre viscous diff? Although it's nominally set at 50:50 front to rear you can see the split oscillating on a 4WD rolling road as it soaks up the driveline shunt. I'd be fascinated to know how to change it.

Josh - Do you have details of the viscous fluid upgrade option?

cms-gt4 · **Posted:** Thu Apr 17, 2014 12:03 am

A guy in Austria handles it. I have bought parts from him before and had no issues. From all I have read I have not found a way to change the power bias of our awd system. The only car I found with a viscous center and a rear bias was a porsche but I could not find any technical docs on the awd system. I think the 3000gt/ gto has an aftermarket center diff that changes the vc bias.
http://www.alltrac.net/phpBB2/viewtopic ... 43&t=36743

Nibbles · **Posted:** Thu Apr 17, 2014 8:41 am

Stiffen the rear / soften the font.

Get a pair of nankangs on the rear.

Jon9985 · **Posted:** Thu Apr 17, 2014 9:49 am

I cant get onto the hyperlink.

I do tend to put the crapper of my crap tyres on rear to allow oversteer and the front to grip. Im going to compete in gymkahna grid again this year and i want to beat the subaru for once that always beats me. His 60/40 split allows him just to get that edge on entry to piroette.
Think i need more practice to but if can upgrade car to help i will do.

The Lorro · **Posted:** Thu Apr 17, 2014 1:51 pm

This is maybe where the Superstrut is actually a disadvantage?

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looking into front diff

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