V8 rear diff wanted

[Error404]

After a V8 torsen rear diff if anyone has one sitting in the garage?

Cheers
Alex

[spink]

this place are/were breaking one

http://www.audivwparts.co.uk/

[Error404]

nice one James

[Error404]

Sorted - its mine! :mischeif:
Good price too!!

[Rusty]

:mischeif:

[Jamo]

*******!

[Error404]

FYI - Just had an email from Sanburn Autos - they have one on the shelf.

Not cheap though - £250 + VAT

[Rusty]

I'd say that was about the going rate, maybe not with the VAT tho.

Why not just cut the wire to the ABS controller and then you can just lock the diff, there's no traction problems with the rear to require an LSD, only if oyu want to go drifting and then a locked diff is better...

[Error404]

Well i paid quite a bit less than that this morning

I'm trying it to couter the inherant understeer in the coupe and make the car more neutral - a combination of a 22mm rear ARB and the torsen should help stop it all together i hope
If I want to go sideways I just rob the girlfriend's RX8, I don't have to pay for tyres then

[Acidburn]

Mine goes sideways easily.... still at least you finally found one, the one I know of will be on the bay so someone might get a cheap one.

[Rusty]

I'm not sure that a torsen rear diff will address that partculary but it'll be interesting to see.

Some ramblings:-

The diff will only lock with whatever speed difference the torsen is set to thus in tighter corners or during wheelspin on one wheel faster than another. When it does lock it could push you straight on, a car with a locked diff doesn't like to turn but it does try and make the car slide because the wheels try and share the slip, if they can't slip then it'll push wide because it doesn't want to turn any tighter. However, it does give you more control over a slide by stopping whichever wheel has less grip from spinning up and losing all grip, hence why powerful cars with not enough grip gain from using one. Also, it will try and make the car slide when it does lock so be careful on those full throttle roundabout exits!

A 26/22 ARB setup will definitely address understeer, I've got 26/25 and will see how twitchy it is on the HnRs but have a 24mm and a 26mm bar sat waiting...

Will be interesting to see how it works Alex, there's not been much comment on them other than they can make the car twitchy (as metioned above and a mate's beemer with an LSD is a 'mare in the wet always trying to slide rather than just spin a wheel up!) and they're weak (both by Audiman) and that you can do doughnuts with them (by Jeffer ), both cars had 500+bhp and thus traction problems that needed sorting, can't say that 300bhp gives the same issues

All of that doesn't mean that I don't want one though

[A80Avant]

it is said though that the V8 rear diff cannot take too much power...it goes bang a little over 400hp...

id say that even with the 19mm Neuspeed RARB i have noticed increase in the neutrability of the avant...and im only in the mild setting

[Error404]

Well I'm hoping the rear ARB should dramatically reduce understeer on turn-in and help to reduce scrubbing wide. I wanted to try the torsen to increase exit grip. As far as i understand whats happening, once back on the power exiting a corner, the first wheel to spin is the inside front. Even my smokey 7A can get that spinning in tight corners. The front open diff allows most of the torque to divert through this spinning wheel, you drift wide. The torsen senses the loss of grip in the front axle and diverts more torque to the rear axle, which then also begins to spin the inside rear, diverting most of the torque through that, there is be a situation reached where both inside front and rear wheels are scrabbling, you loose grip and you scrub wide.

My theory on using the torsen was that once the inside front wheel starts to loose grip, the torsen centre diff sends more torque to the rear axle - becasue the rear torsen can distribute the power to both rear wheels more efficiently, inside rear wheel spin should be stopped almost entirely, the car should divert majority of torque away from the scrabbling front axle and be able to get it down at the rear, reducing understeer and stopping the front end scrubbing wide. I'm not hoping for a massive change with the 7A but once the chassis, suspension and brakes are sorted, i'm going to swap in a 20vt, then it should make more of a difference in getting the power down.


Of course my theory is probably seriously flawed and its probably my lack of driving talent that is my problem anyway. Unfortunately I can't buy skill from a breakers yard

[S2central.net]

@Error - I think your description is pretty good theory there actually - based on a quik read thru here... LSDs (like Torsen) transfer the torque from the wheels that slip to the wheels that grip - unfort I can't take credit for that wonderful one liner - It was a Japanese company famous for Blue rally cars, gold wheels and the numbers 555 !

I've had a V8 torsen resting in the garage for ages and I've almost forgotten who did a deal with for a 7A diff housing to put it into - I dont wanna mess with my OE S2 one... Need to get up to speed on this again for the winter tasks...

[Rusty]

Hmm, my issues are always with the front inside spinning and keeping spinning, never had an issue with the rear in any situation, even trying to really P it off in the wet. I do wonder if my centre diff is a little tired...