[QUOTE=Spektre;687682]^^^ will try, how do you make sure its 3.9 or 4.1 though steve?[/QUOTE]

If you can't work it out from one rotation, try two rotations and look for 7.8, 8.2, or 8.8 rotations of the propshaft.
Earlier you said you had 400 rotations of the front wheels, and only 10 on the back. Are you sure it isn't FWD? haha! If I wasn't rallying this weekend, I would come up to your place and give you a hand.

Wavey.

[QUOTE=Spektre;687566]ok... fucked day...


Great... drive over there, saw for myself and exactly as they described. In 4th the front hubs at the start at around 400 revs with the rear at about 10??? as you accelarate the rears catch up to the fronts but then it hits a RPM (dont know exactly, around 4000ish) and the rears make the dyno skip, like its over compensating.

...[/QUOTE]


Just thinking out loud here, if the front and rear hubs are rotating as you say "400 revs and 10 revs" then your centre diff isn't working correctly. Maybe when it gets up to speed the little amount of LSD action that the centre diff still has working has brought the rears up to speed, but if the rear diff is the wrong ratio, then this is causing the skipping that you speak of??
I'm sure the wrong ratio rear diff would also quickly shag a centre diff, if it would drive at all. But once the centre diff is shagged, then it may drive ok, without you noticing because the centre diff is now open, and has no LSD.

Just ideas on what could be wrong.

Also I'm pretty sure you can swap gearbox internals, so the Gearbox code may say that it should be 4:11 but it might be something else.

Wavey.

[QUOTE=Kato;687706]Contacted the seller and asked them to confirm what is in the car?[/QUOTE]


did that mate, the guy we bought it off is a mechanic and all the stuff was in iot when he got it 2 years ago. He's had it on a rolla dyno and flogged it around Phillip Island heaps of times. No issues.

treat me as a noob too, but isnt the centre diff inside the gearbox?

What did evo r say about it? They are the machanics.

Just had a chat with Doug at Stechnic and as always he came up with the goods. To note, Wavey had it pretty close...

Sounds like the diff is the wrong ratio and hasd put pressure on the viscous coupling and blown it out so now is a free flowing centre diff not a LSD like it should be.

Check diff ratio tonight, see if problem if so, new diff and viscous coupling...

just seen this link, nice car guys, sorry to hear your having difficulties, nothing like a GC8 to provide difficulties.............
Mines running well now, loving the new ride height, just got some new wheel so once i get tyres i'll pop up to show you.

in the interim if u need any help give me a shout?

regards

Blash

I have a 4:11 diff for sale if you need it cheap cheap !! Pm for details.

Sent from my GT-I9100T using Tapatalk 2

[QUOTE=seagull;687627]I was going to try the 3rd gear take off seeing I have the bat man outfit. Its the one you borrowed from me last week. Geoff borrowed it a few weeks before, but as you know he is half asian and 5 foot 2 so he had to roll the arms and legs up. :)[/QUOTE]

HEY! I see what you guys did there. :icon_batm

update time...

so our wrx is a FWD car... no, literally. The viscous coupling is fucked, turning the fronts while all car suspended rears dont turn at all.

Rear diff is also 4.44 ratio, not 4.11 as it should be. This would of been putting pressure on the viscous coupling and blown it.

so, will be ringing Doug in the morning to organise a viscous coupling and see if he wants to trade a 4.44 diff with a 4.11...