Feeler thread - Group buy on Mk2 TT lower arms...................

[danishmkvgti]

Is anyone able to clarify what the situation is with R32 front suspension? I'm assuming its the same as the S3 but it would be nice to know for sure. If I can shed some weight, every little helps!

when it goes wrong it goes really wrong, second set of bolts for the S3 front alloy hubs and carrier for the caliper was ordered with r32 partnumber: they are the same as the gti, so to answer your question, r32 front hubs must be steel as the gti's, sorry 

[animal]

Is anyone able to clarify what the situation is with R32 front suspension? I'm assuming its the same as the S3 but it would be nice to know for sure. If I can shed some weight, every little helps!

when it goes wrong it goes really wrong, second set of bolts for the S3 front alloy hubs and carrier for the caliper was ordered with r32 partnumber: they are the same as the gti, so to answer your question, r32 front hubs must be steel as the gti's, sorry 

Cheers, that's a start. I'll add S3 hubs to my list as presumably they are a direct swap as the brakes are the same? Need to find out next if the arms are ally or steel.

[excursion]

FYI Mk5 R32 Front Hubs and lower arms are Cast Iron.

2008 < R32 Rear hubs were cast iron with a tubular Aluminium Subframe.
2008 > R32 rear hubs went to Forged Aluminium and the diff cradle went to tubular steel (I suspect the goal was reduced unsprung weight and offset additional cost offset by using a cheaper subframe).

See my findings here: http://www.mwstewart.co.uk/articles/mk3fiestaquattro/ half way down the page.

I'm using the Alu. Rear subframe with the forged hubs, TT front arms and S3 hubs. The weight of the cast Iron parts is simply obscene!

Also FYI this is the data on which I based my component choice:

Front
Track width is 13 mm wider.
springs, dampers and anti-roll bars are of a different rating
ball joint fastening bolts are integral parts of a separate retaining element - this must be replaced each time the bolts are loosened.
The ball joint is in a lower position - the result is a higher centre of roll.
A tubular anti-roll bar is used on models with front wheel drive, while a solid bar is used on quattro models. The link rod is a carry-over part from the Audi A3.

Rear
The wheel carriers, damper bearings and wheel bearings are modified versions of the components used in the Audi A3. Track width has been increased by 15 mm on each side over the Audi A3.
The wheel carrier has been modified geometrically in order to increase track width.
Note - There are three generations of wheel bearings, 3rd comes in around 2008.

Steering
new track rod outer joint with larger joint diameter and modified journal geometry
reduced steering angle, steering rack shortened from 80 mm to 78 mm
new control unit due to new control software without dsr function
In the case of the Audi TT, the power steering assist maps are determined by the powertrain type (front wheel drive or quattro) In the case of the Audi A3, the weight of the front axle is the determinant factor.

[DaveB@Vagbremtechnic]

Excellent first post. ......lots of good info there.

[excursion]

Thanks Dave, I should have stated that the list of modifications in my post refers to the TT.

I'd be interested to hear if anyone has experimented with Mk6 Golf suspension. I think VW quote a Camber or Castor change for the Mk6, I suspect either the top mount or rear wishbone bush was modified - does anyone have info on this?

[RedRobin]

^^^^
Based on that top class info, does changing a GTI's front wishbones to the Audi TT's not get fully exploited because of the GTI's different steering mapping? [I hope my question makes sense]. Or does the steering mapping instruct S.M.A.R.T-ly so it wouldn't matter?

[excursion]

^^^^
Based on that top class info, does changing a GTI's front wishbones to the Audi TT's not get fully exploited because of the GTI's different steering mapping? [I hope my question makes sense]. Or does the steering mapping instruct S.M.A.R.T-ly so it wouldn't matter?

I wouldn't worry too much about the steering calibration.

I would recommend fitting TT Hubs, TT Track rod ends, and TT lower arms as a package - this will give a great all-round benefit (additional track, camber and roll-centre change).

Fitting the TT lower arms to a GTi will provide additional track and camber adjustment, but the roll-centre will remain unchanged. The roll centre change will make the biggest difference to handling.

[RedRobin]

I would recommend fitting TT Hubs, TT Track rod ends, and TT lower arms as a package - this will give a great all-round benefit (additional track, camber and roll-centre change).

Fitting the TT lower arms to a GTi will provide additional track and camber adjustment, but the roll-centre will remain unchanged. The roll centre change will make the biggest difference to handling.

....I'm now wondering if my AP Racing brake kit would fit the TT hubs. The slippery slope of modding, eh?

[excursion]

....I'm now wondering if my AP Racing brake kit would fit the TT hubs. The slippery slope of modding, eh?

The TT hubs are designed to accept the same brake packages as the rest of the 8P/Mk5 platform; your AP's will go straight on.

[RedRobin]

....I'm now wondering if my AP Racing brake kit would fit the TT hubs. The slippery slope of modding, eh?

The TT hubs are designed to accept the same brake packages as the rest of the 8P/Mk5 platform; your AP's will go straight on.

....Thanks I was afraid you were going to say that! I'm trying to stop modding my car: I've already got KW-V3 coilovers, Whiteline anti-lift kit, Eibach ARB's, Quaife ATB diff, and AP brakes and OZ lightweight 8kg wheels.

[QD MBE]

RR,

In my travels, I looked at fitting the S3 hubs to my car, didn't in the end. 

I did however notice that the mounting bosses for the caliper carrier were significantly thicker on the S3 hub (alloy) v's the GTI (cast iron) hub.

The S3 hub carrier mounting spigot was in the region of about 10mm thicker.  I sent a hub up to the Reverend Brake (DB) for him to measure and manufacture a set of Caliper carriers (for Porker 996TT calipers) taking into account the difference in thickness.  This difference will alter the centre line of the caliper, and hence the disc will not sit in the centre of the caliper.

Hope that makes sense.

[RedRobin]

^^^^
Cheers Stokey

Yep, it makes sense and tells me not to go beyond just the TT arms mod.. Can of worms which can be sorted, but.

Afterall, look what happened to you: Started with Porsche calipers and ended up with a whole Cayman S car!

Love your "The Reverend Brake" title for DB

[excursion]

Mounting lugs are indeed thicker but the additional depth is offset towards the bolt side, thus you'll need longer caliper bolts but the calipers will remain the same.

It doesn't make sense for VAG to make a replacement hub that dictates the use of different discs and caliper carriers.

[QD MBE]

Have to agree to disagree.

I know that when i tried to fit my Porker 996 TwinTurbo calipers to a set of S3 hubs I had, it would not get anywhere near.

Some of the BBK's rely on the carrier being mounted on the other side of the mounting spigot, to allow for the deeper caliper (2 piston v's 4 piston).

Welcome to the forum BTW.
 

[DaveB@Vagbremtechnic]

Excursion, the S3/TT/R32 brakes are indeed interchangeable but upwards of disc assembly heights of about 48mm it makes more sense to bolt the carriers on from the other direction which forces a pretty thorough redesign.

We're running disc assemblys of 50mm + to try to give clearances for some of the larger 4pot brakes and we've no choice but to bolt on from the other way.

Its only in the last 8 weeks or so AP racing have done a kit for the S3, the gti kits been out for a while.

I'm just redesigning one now for one of our S3 chaps on here