Why T181 flanges

[Tom Alltypes]

You have 15 tooth side gears instead of 17 tooth, which takes the 10 tooth spyders instead of the 11s, the strongest VW made. And they were spliced to 091 splines. GOOD parts!

[SilverBullet]

I am in the process of building the rear setup using 86 944t alu. trailing arms. These are the parts I've collected,
1.86 944turbo alu. trailing arms with stub axle
2.86 944turbo complete rear axle with cvs (100mm)
3.181 output flange to mate to the irs transmission.
Are these all the parts I need to put this together?

[Pillow]

Good info Pete! I have not seen that setup before with those output shafts.

Silver, yes that is all you need to get the drivetrain going.

[Wally]

Originally posted by Pillow
Silver, yes that is all you need to get the drivetrain going.

I hope the 944 turbo axles are longer then the bug ones, otherwise you need T3 bus (vanagon) axles. Those also have 100mm CV joints and have the right length. At least that is my experience...
Cheers,
Walter

[zen]

i'm still so confused. the T1, T2 and 944 axles all have different lengths. the early ali arms with full brakes add 1 3/4" per side. i do not know if there is added distance between the trans and the inboard side of the stub axles to know which is the right length axles to use. this of course would help if i had any part in hand, but i am doing this all on your guys info so far.

johnh is brining me a setup off this weekend of a drag car to try and fit. it would be great if anyone can clarify before i head up to this show this weekend though so i can get this stuff at the swap. just seems like everyone is using a slightly different setup.

let me add that i am fine with using T1 output flanges. from what i have seen, it is all a matter of degrees and i do not plan on beating up my tranny too terribly bad. so if using T1 flanges, what do i need to go out from there to the stub axle?

[SilverBullet]

Yes, Wally, the 86 944turbo axles are longer than the T1 axles.
From what I understand, correct me if I'm wrong, using the 86 944turbo aluminium trailing arms,
1. use either the 86 944turbo axles with the cv joints( 100mm) and with the 181 output flange at the transmission,
2. T2 bay window axles with cv joints ( 100mm ) and with the 181 output flange at the transmission.
Think its more difficult to mix and match 2 different cv joint sizes (ie, 90mm T1 and 100mm T2 or 944 or 912,914) on the same axle.

Cheers.

[Pillow]

Here is what I would do:

IRS Tranny > T1 output flange > T1 CV > long 944 axle '87 up > T1 CV > T1 stub axle

* From my understanding the T1 and T2/944 CVs are interchangable on the axle splines. I hope so as I have assumed this in my conversion, but not had the chance to mock up the axles on the T2 CVs... Granted I am 99.9% sure it will work.

[SilverBullet]

The dia. of the axles are different. The 86 944turbo axle dia. is 27mm, the dia. of the T1 axle is 24.4mm. I don't know if the T1 axle will fit the 100mm cv joints (ie T2, 944...). as there is a difference of 2.6mm! What say you guys?

[SilverBullet]

The dia. of the axles are different. The 86 944turbo axle dia. is 27mm, the dia. of the T1 axle is 24.4mm. I don't know if the T1 axle will fit the 100mm cv joints (ie T2, 944...). as there is a difference of 2.6mm! What say you guys?

[zen]

we are heading in the right direction. i wish i could be of more help by being able to have parts in hand. i will soon. should be getting some this weekend. i like pillow's idea if it works just because i am able to reuse so much T1 stuff and keep it cheap and still strong enough.

[SilverBullet]

Don't you think that using an aluminium trailing arm, you want to use bigger and stronger cv joints and axles, especially one with a big engine and also going through all the effort to use the wider trailing arm?

[zen]

i don't see the corelation to wider ali arms and beefer CVs, but i do with a bigger engine. no one has demostrated a real NEED for it though. many drag racers are pumping much more HP than i will be and still use T1 stuff all the way through. i have no problem bumping up if it is needed, but i am not hearing that so far. also no reason not to do it if you want though.

given, 951 brakes aren't really NEEDED, but they have a visiual wow factor at least.

[SilverBullet]

Ok, here are some measurements, 86 944turbo axles: dia:27mm length 540mm, T1 axles: dia 24.4mm length 420mm. (+/-1-2mm) . I don't have the T2 measurements but would say close to the 944 axles specs. .

[SilverBullet]

Oh yes, the 86 944turbo trailing arm's stub axle uses 100mm cv joints and cannot be interchanged with 90mm stub axles so unless one can find an axle shaft that accepts 100mm cv on one side and 90mm on the other, to be use with T1 axle flange at the transmission, I don't see how on e can use just the longer axle shaft with wider arms and still use 90mm cv joints. Correct me if I'm wrong or any other suggestion?

[Wally]

Gentlemen,
The 944 turbo axle has porsche pline pattern, the VW T3Bus/Vanagon axles have VW spline pattern, thus allowing 100mm VW CV's on one side and 90mm Type 1 CV's on the other side. I've run them now in that configuration for two years, so yes, it works fine and I agree with Zen, that you are more likely to break your trans - even if it is reinforced - first than you will break a 90mm CV...
So, the Vanagon axle has the right length for a 944 turbo alu arm and a type 1 trans.
Good luck,
Walter