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TTRS Clutch Options

115K views 282 replies 53 participants last post by  JMBone 
#1 ·
Hey guys, looks like I'll be in need of a clutch sooner than later. Went out today with my stage II on the highway and slipped pretty good a couple of times, especially when cold. It seemed to hold better when everything was hot, which I find strange.. Anyway, the only options I see for aftermarket clutches is a four puck from APR and a clutch that was used in this build (http://www.redlinespeedworx.com/apr-ttrs-stage-3-build-gtx-3576-650hp-daily-driven/).

Having a 6 puck in previous cars, I'm not sure I want something that hardcore in the TTRS in terms of engagement. I don't mind a stiffer pedal as long as I can slip it. Should I look at options in the UK?

Thanks!
 
#2 · (Edited)
How obvious was your clutch slip when cold? Any videos?

I've done some research on the clutch options, and there isn't a clear best option. Some options are:

1) Stock. Many folks report success running the stock clutch on stage 2 (and even stage 3) TT-RS cars if you don't do aggressive launches. There are no reported holding torques published, so it's hard to compare when you get with the "upgrade" clutches over stock. One thing that is great about the stock clutch is that it has a self-adjusting mechanism built into the pressure plate that adjusts for disc wear to keep the preload / engagement consistent. I've yet to see an aftermarket clutch that includes this, which can result in issues down the line as you wear down the disc.

2) Sachs "performance" pressure plate + organic disc. This is rated for "550+ N*m", which is equivalent to 406 ft*lbs. That's barely over the stock torque of ~360 ft*lbs, and well below even a Stage 1 reflash. So again, it's not clear what this clutch buys you over stock, since stock is also organic. Note that most all of the aftermarket clutch options use this Sachs "performance" pressure plate and repaint / rebrand it, with different disc materials. I assume this clutch holds more than stock, and Sachs underrates it. This retains use of the stock dual-mass flywheel. http://www.sachsperformance.com/Sac...-quattro-250-kW-;-05/2009-:::2_3_538_539.html



3) Sachs "4-puck" racing clutch disc. This is what APR recommends (it supposedly holds 600+ ft*lbs). But due to the reduced friction area, this clutch will not last anywhere near the length of a stock clutch (far less total material that will wear more quickly over time). The 4-puck clutches are known to have more harsh engagement and some chatter when feathering from a start at low RPM. This retains use of the stock dual-mass flywheel.



4) DXD / South Bend clutch kits. From what I can tell, DXD / South Bend takes the Sachs "performance" pressure plate, paints it red, and then takes OEM discs and removes the center spline section (to re-use) and attaches their own friction materials (depending on the "stage"). I've heard that they have versions that retain the dual-mass flywheel, but most installs seem to go with a single-mass flywheel replacement. The latter has various NVH and engagement smoothness impacts (nothing I wanted to compromise for a daily driver).

5) Dual-disc clutch from 034 Motorsports (Clutchmasters unit currently). 034 is testing their own custom clutch solutions for the TT-RS. I'll let them chime in on any issues with their setup, but IMO this is an "aggressive" racing solution, not a daily driver (it requires changing to a single-mass flywheel).

6) Dual-disc clutch from Helix (UK). They currently make a "race" version that is 215mm in diameter and requires a flywheel change to single-mass, and is unsprung. A few folks in the UK are running these (including "johnnyc"). The "puck" version holds 870 N*m (641 ft*lbf), while their organic face version holds 700 N*m (516 ft*lbf). They are supposedly working on a "street" version in a larger 228mm disc that allows them to fit springs in the twin plate config for smooth engagement for road cars. I suspect though that hanging all of this inertia off of the transmission will be a problem for the synchros, which were designed for a light unspring disc (and a sprung dual-mass flywheel instead).

7) Dual-disc clutch from APR (still in development with no clear timeframe). This is supposedly a carbon/carbon clutch disc setup, with serviceable carbon friction surface inserts. Hard to tell much else until more info is released, but if it's anything like the Stage 3, it will be a long time in the making (and of course worth the wait for those that do).


So after all of that, I'm tempted to just stick with stock (or replace stock with stock if I have slipping issues), because:
1) stock is designed to work with the dual-mass flywheel
2) the stock pressure plate auto-adjusts for even loading / release control as the disc thickness changes over life as it wears

Last thing I want to do is put in an aftermarket clutch, have it work fine today, and then start slipping / develop issues as it wears (plenty of horror stories of those online).

Any other folks have solutions they can share?
 
#4 ·
How obvious was your clutch slip when cold? Any videos?

I've done some research on the clutch options, and there isn't a clear best option. Some options are:

1) Stock. Many folks report success running the stock clutch on stage 2 (and even stage 3) TT-RS cars if you don't do aggressive launches. There are no reported holding torques published, so it's hard to compare when you get with the "upgrade" clutches over stock. One thing that is great about the stock clutch is that it has a self-adjusting mechanism built into the pressure plate that adjusts for disc wear to keep the preload / engagement consistent. I've yet to see an aftermarket clutch that includes this, which can result in issues down the line as you wear down the disc.

2) Sachs "performance" pressure plate + organic disc. This is rated for "550+ N*m", which is equivalent to 406 ft*lbs. That's barely over the stock torque of ~360 ft*lbs, and well below even a Stage 1 reflash. So again, it's not clear what this clutch buys you over stock, since stock is also organic. Note that most all of the aftermarket clutch options use this Sachs "performance" pressure plate and repaint / rebrand it, with different disc materials. This retains use of the stock dual-mass flywheel. http://www.sachsperformance.com/Sac...-quattro-250-kW-;-05/2009-:::2_3_538_539.html

3) Sachs "4-puck" racing clutch disc. This is what APR recommends (it supposedly holds 600+ ft*lbs). But due to the reduced friction area, this clutch will not last anywhere near the length of a stock clutch (far less total material that will wear more quickly over time). This retains use of the stock dual-mass flywheel.

4) DXD / South Bend clutch kits. From what I can tell, DXD / South Bend takes the Sachs "performance" pressure plate, paints it red, and then takes OEM discs and removes the center spline section (to re-use) and attaches their own friction materials (depending on the "stage"). I've heard that they have versions that retain the dual-mass flywheel, but most installs seem to go with a single-mass flywheel replacement. The latter has various NVH and engagement smoothness impacts (nothing I wanted to compromise for a daily driver).

5) Dual-disc clutch from 034 Motorsports (Clutchmasters unit currently). 034 is testing their own custom clutch solutions for the TT-RS. I'll let them chime in on any issues with their setup, but IMO this is an "aggressive" racing solution, not a daily driver (it requires changing to a single-mass flywheel).

6) Dual-disc clutch from Helix (UK). They currently make a "race" version that is 215mm in diameter and requires a flywheel change to single-mass, and is unsprung. A few folks in the UK are running these (including "johnnyc"). The "puck" version holds 870 N*m (641 ft*lbf), while their organic face version holds 700 N*m (516 ft*lbf). They are supposedly working on a "street" version in a larger 228mm disc that allows them to fit springs in the twin plate config for smooth engagement for road cars. I suspect though that hanging all of this inertia off of the transmission will be a problem for the synchros, which were designed for a light unspring disc (and a sprung dual-mass flywheel instead).

7) Dual-disc clutch from APR (still in development with no clear timeframe). This is supposedly a carbon/carbon clutch disc setup, with serviceable carbon friction surface inserts. Hard to tell much else until more info is released, but if it's anything like the Stage 3, it will be a long time in the making (and of course worth the wait for those that do).


So after all of that, I'm tempted to just stick with stock (or replace stock with stock if I have slipping issues), because:
1) stock is designed to work with the dual-mass flywheel
2) the stock pressure plate auto-adjusts for even loading / release control as the disc thickness changes over life as it wears

Last thing I want to do is put in an aftermarket clutch, have it work fine today, and then start slipping / develop issues as it wears (plenty of horror stories of those online).

Any other folks have solutions they can share?
Thorough and supported with great info...:thumbup::thumbup::thumbup:

You should have been an engineer...:)
 
#3 ·
See response here by Simon. On the last Trackday back in October he did say his car felt good.

The factory option is the alternative as it would appear that there are still few options on the market at present.

Mine felt like it was slipping some time back however I have had no further issues for a good 20k miles now – am at 58.4k miles at present.

The feeling I got when I thought the clutch was slipping was simply no drive when applying power though revs just built up.

Ohh, and I had a horrid burning smell which lasted a couple of days - as I say, that was a good 20k miles and all been well since.

The thing is to check requires a fair amount of dismantling the car so the best option was to continue driving until failure then we will replace with factory (OE) parts again.
 
#7 ·
That's pretty slick with the stock adjusting pressure plate, never seen anything like that before, go figure! :) I wonder if that's another trade off and will cause reduced clamping force when the disk wears. I wonder if a standard style PP would clamp better...but what happens when the disk wears and there is no adjusting screw on the pedal to adjust for it manually (since its designed to be auto adjusting on the pressure plate). Yes, I see what you mean by keeping the stock style clutch. Ideally, I'd think keeping the stock organic disk and dual mass flywheel but go with a heavy duty pressure plate. This is not an easy decision and we know the labor involved to try experimenting can be costly.
 
#10 · (Edited)
1) I managed to completely slip my clutch playing around with the Launch Control feature in my UM Stage 2 tune. The car wouldn't move under its own power until it cooled down. Smelled like burnt clutch for weeks afterwards. It drives okay now, but I don't trust it for full power/attack/track mode type driving.

2) I have a 215mm twin plate, organic clutch and steel flywheel kit from Helix Motorsports UK sitting in my garage, ready to go in the car. Helix was great to work with via email. They answered all of my questions and provided information so that I could decide which clutch setup would be best for my usage. The 215mm twin plate/disc clutch and flywheel kit from Helix weighs about 13.5Kg. If I want to go more to a more aggressive clutch setup, Helix can provide the paddle type clutch discs to install, using the same clutch cover assembly as the organic disc kit. The proof will be once I have the Helix twin plate/disc clutch installed, but so far I would highly recommend Helix Motorsports UK.

3) At independent VW/Audi shops, I have gotten quotes ranging from $1000-$1200 to R&R the clutch (price is without any parts). I am either going to do the clutch install myself or break down and take it to a shop for the work around the first of the year.

4) Sachs does offer a HD, uprated pressure plate for the stock DMF. However, if you read the specs, the Sachs units are not rated for the torque of a Stage 2 or 3 TT-RS. Yes, they may "work", but you are going to be pushing the clutch past its design limits.


One additional point regarding the options from Helix... The original "race" version was 200mm. The new, more street friendly version is 215mm, not 225mm. This is per an email sent directly to me by one of the Engineers who works for Helix.
 
#12 ·
One additional point regarding the options from Helix... The original "race" version was 200mm. The new, more street friendly version is 215mm, not 225mm. This is per an email sent directly to me by one of the Engineers who works for Helix.
Interesting. Accordingly to my conversations with the Helix engineers, their current 215 mm version was designed to be "used for racing", even though they have an organic version available that holds less torque than the puck type (700 N*m vs. 870 N*m). They also specifically said they were working on a 228mm version for pure road cars (the street version) that will take 6 months+, and would have a sprung center (vs. the solid center of the race 215mm version).

I'm pretty sure that what you have is the existing 215mm solid center race version, but with the organic friction surface.
 
#11 ·
Slipping clutch

I have also experienced the soft clutch syndrome after a track day up at willow springs while driving home on the highway. I got home and went through all the options like you are now. However, I have yet to experience the slippage again. I spoke with the folks at Loba motor sports and they basically told me that there really isn't a clutch option that is mellow for the street at this point. The engagement on the sachs unit and anything that clutchmasters has to hold the torque will be annoying if you are dealing with any hills or traffic on the daily commute. I am in san diego and often experience the joys of bumper to bumper traffic on the i-5, so there is no way I could possible do it. If it happens again, I'll probably just replace the clutch with a stock unit.
 
#18 ·
Here are couple of additional pictures of the actual Helix 215mm twin disc organic faced clutch kit which I have for my TT-RS. The plan is to have it installed by early Jan. I will post up results.



 
#19 ·
Effect of temp on torque for APR Stage 1 and 2

Colder temperatures raises the torque considerably and I assume that is pushing some cars over the 475 lb ft clutch limit. Has anyone measured the torque increase with temperature, such as winter driving on APR stage 1 & 2? Does the APR software limit the torque increase as temperatures drop to winter levels? Assuming very little knock at winter temps, what is the limiting factor for generating and transmitting torque - software, fuel or fuel cut, clutch capacity? Seems like more engine control might be needed to reduce clutch slippage in cars that get driven in the winter.
 
#22 ·
Colder temperatures raises the torque considerably and I assume that is pushing some cars over the 475 lb ft clutch limit. Has anyone measured the torque increase with temperature, such as winter driving on APR stage 1 & 2? Does the APR software limit the torque increase as temperatures drop to winter levels? Assuming very little knock at winter temps, what is the limiting factor for generating and transmitting torque - software, fuel or fuel cut, clutch capacity? Seems like more engine control might be needed to reduce clutch slippage in cars that get driven in the winter.
Where did you hear the 475 ft*lbf stock clutch limit? I haven't been able to find any concrete info on this.
 
#20 ·
Thanks for the pictures and information guys! The Helix website doesn't reveal very much. I look forward to hearing your experiences with it, especially if there is any extra transmission wear with the (assumed) extra mass and unsprung plates. I don't know first hand, but isn't there more potential to damage a gear?
 
#21 ·
The Helix kits are in the 12.5Kg to 13.5Kg range and much lighted than the OEM flywheel/clutch combo. Also, the Helix kits have a much lower moment of inertia (MOI) than OEM. The overall effect is to allow much faster shifting than the OEM flywheel/clutch combo. Watch the videos of JohnnyC shifting his 6spd Stage 3 TT-RS at very close to DSG speeds!

The disadvantages of not having sprung clutch plates are going to be the potential for transmission gear clattering or roll over noise AND more shock to the driveline when engaging the clutch. A sprung clutch disc (or dual mass flywheel) absorbs some of the power spikes which one gets in the power delivery of an engine. These power spikes are worse with less cylinders and generally lessen with more (depends also on the offset angle of each crank throw for piston/con rod assemblies).

I will definitely post up results regarding any noise, vibrations, etc, along with overall impressions once installed.
 
#23 ·
Ah, thanks for the explanation. So if it really is just NVH and a tad more shock being transmitted, would there be any reason to choose the sprung dual mass they are working on? My only concern was modulating the clutch in some traffic and reliability with repeated hard launches/track use. I think the one you got sounds like a good compromise, unless the shock to the driveline is really a big deal.
 
#26 ·
475 lb ft clutch limit

Several threads from APR stated that they fairly consistently hit a 475 lb ft limit before the OEM clutch slipped. In some cases the clutch held more than 475 lb ft initially, but eventually slipped consistently at 475 lb ft of torque. It's important to note that the 475 lb ft limit they found was Wheel Torque, and not engine torque, which would be at least 10 - 15% higher at the flywheel.
 
#27 ·
Several threads from APR stated that they fairly consistently hit a 475 lb ft limit before the OEM clutch slipped. In some cases the clutch held more than 475 lb ft initially, but eventually slipped consistently at 475 lb ft of torque. It's important to note that the 475 lb ft limit they found was Wheel Torque, and not engine torque, which would be at least 10 - 15% higher at the flywheel.
Hmm so then there is a good chance that the Stage 3 on 91 octane will hold with the stock clutch (455 ft*lbf at the wheels). 93 octane hits 495 ft*lbf.
 
#31 ·
I dont think its a matter of luck, more so to do with a lazy driving style or poor clutch control under launching from what ive seen/read.

3 of the UK's hardest road driven TTRS never had OEM clutch issues, even whilsts snapping propshafts, breaking gearboxes,breaking driveshafts, engine mounts and rear diffs, all whilst being used on the OEM clutch.

All 3 cars where used as developement vehicles at some stage, had numerous drag strip visits, did v-max events, auto cross, and two of the cars participated in weekly nightime london races.

And all 3 cars had something in common, when at wide open throttle, none of the drivers would do so at low rpms, 4500rpm upwards only, making use of the gears.

The OEM clutch even held up pretty decently to early development APR stage 3 abuse, and did well in a australian GTR beating TTRS rally car.

My helix twin plate paddle clutch has been fitted, perhaps i'll give some feedback this weekend if road conditions allow
 
#33 ·
Hey Guys,

I'm in the same boat as Optimus, Stage II, 21k miles, with slippage in the higher gears. I use the car as a daily driver in San Francisco (hills and traffic) but also do a lot of autox, track days, and pretty aggressively on the twisty roads near here.

I've been working with the guys at 034 Motorsport to find a solution. I was planning on the SACHS kit offered through APR but having read this thread I'm second guessing that decision.

Here's what the guys at 034 have to say:


"A stage 2 car shouldn't be slipping unless its an avid track car then maaaaybe."

Having said that we found a southbend pressure plate with greater clamping force and he sad that with an oem clutch disc would be good. I have to speak with Southbend still but i think this is the best bet.

Then i brought up the APR sachs set up and he said they work great and the only reason they are rated lower is because its just that an arbitrary number...but that the springs on the sachs are stronger than that of OEM so that too is another viable option.

Let me know what you think...I will still contact Southbend tomorrow when i get in and find some more liturature on the APR one."



What do you guys think?
 
#34 · (Edited)
I've gone through this entire thought sequence, and came to the conclusion at the Sachs Performance units are the best bet currently for a daily driver. For a Stage 2, the Sachs Performance organic clutch kit is the way to go (IMO). Even for a 91 or 93 octane Stage 3 car I'm convinced that this clutch will be fine for non-race applications.

I hear the 4-puck Sachs clutch isn't that bad, but I don't want any engagement smoothness compromise. So I'm moving forward with the Sachs organic setup (should be installed within 3-4 weeks) and will report back.

 
#37 ·
I'm not sure what the manual clutch is rated at,but the DSG was designed up to 600 NM ,so it's real limits but with more wear will be much higher.
Plus I think there's a lot of trick software at work with the DSG,that can limit engine torque.
I would love to know what my car is pushing out at the moment,especially now the weather is getting colder.
Clutch seems fine though.
 
#39 ·
clutches are only as good as the drivers

i have a tdi golf stock it was 155ftlb now its over 330torqs, 100k on the clutch lots of autox and its still fine

ttrs no problems yet either apr stg1

if you need to rev to 2k while starting from a stop, dont rev match when downshifting, slip it while upshifting, wot at 2k, then all that is bad lol can you say glazed :)
 
#40 ·
There is more to it than just drivers... The TTRS clutches seems to either work exceptionally well or start slipping with little correlation to modifications. Reports of stock cars with slipping clutches aren't unheard of, yet others continue to work with stage 2 or even stage 3 type power enhancements.

It is a fact that the OEM clutch isn't rated for modified torque levels. Though the Sachs options do provide improvements in torque capacity, neither is rated for stage 2 or 3 levels, especially with the newer tunes from APR, UM, etc which provide a much higher torque hit lower in the rpm range than the first generation tunes. Also, paddle type clutches aren't going to last very long when driven on the street in stop and go traffic due to fast wear rates when slipping the metallic friction material.



Sent from my SCH-I535 using Tapatalk
 
#42 ·
The clutch in my TT-RS with a UM Stage 2 tune also slips using NLS, especially after I seriously over heated the clutch trying out Launch Control a few months ago.

(In response to a number of different posts in this thread)

Update from my (email) discussion with Helix Motorsports:

Per Helix, their current clutch options for the TT-RS are geared to race or track usage, so the extra weight, cost, and complexity of an auto adjustment mechanism didn't make sense for their current designs for the TT-RS. They haven't had anyone ask about (until now) or report problems with not having that feature with the TT-RS clutches to date (their first TT-RS customers may not have been looking for a 100k mile clutch either). As reported previously, they are developing a larger diameter clutch geared towards street usage (it wasn't clear whether it will or will not auto adjust) for release next year.

The contact at Helix is going to reply back with more detailed information on the impact of not having an auto adjustment mechanism in their race/track clutches when the car sees more street usage. With the hydraulic clutch system in the TT-RS, he thought that there wouldn't be any problems, but is going to research the question further.

FYI... Clutch torque holding capacity can be calculated fairly easily if one knows the clamping force and the coefficient of friction for the clutch facing.

Thanks

Sent from my Nexus 7 using Tapatalk
 
#45 ·
Marty, I assume you will be mating this clutch to the factory DMF? Very cool to hear you are going stage III, yes let us know how it goes. You having a local shop do the install?

Sent from my Nexus 10 using Tapatalk 4
 
#46 · (Edited)
Yeah the Sachs clutch is designed to mate to the stock DMF. I'm debating whether or not I need a new DMF (car has 27k miles), since the flywheel is $1.1k new! Plan currently is to leave the used stock one in there depending on how the wear looks.

I'm having a local shop do the install. I wanted to install it myself, but just didn't feel comfortable pulling the trans out of the car in the garage for the clutch install portion.
 
#48 ·
Thanks for all the info Marty!

I'm also going stage 3 (my Loba kit showed up today) and I am aggressively looking for a clutch option. Loba is also developing a clutch option that is "street-able" however they are months out of production.
 
#54 ·
I'm not sure on the torque actually, I think it's 560lbft but I could be wrong, I haven't actually dynoed the car yet but we basically know what power it's kicking out by comparing the data logs to that of jonnys car.
 
#55 ·
Ok I've just checked and you are right.

650+hp and 640+ lbft of torque.

No wonder I feel like the car could do a superbike damage
 
#57 ·
loba kit

hey Marty, giac is going to be doing the tune. As far as the clutch options, I'm anxious to hear a review of the new clutch set up you just received. You live in the SF area do you not? Just asking because the hills and traffic in the city are perfect testing grounds for a street-able replacement option for our cars.
 
#60 ·
hey Marty, giac is going to be doing the tune. As far as the clutch options, I'm anxious to hear a review of the new clutch set up you just received. You live in the SF area do you not? Just asking because the hills and traffic in the city are perfect testing grounds for a street-able replacement option for our cars.
I'll definitely give it a thorough testing in stop and go freeway traffic and hill starts. :)

I'm very interested to see the pre and post dyno results with the GIAC tuning. There doesn't seem to be any straight answer on how much gain can be squeezed out of the Loba modified stock turbo setup. When will the tuning start?
 
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