Clutch on 997 GT2 - Page 3 - Rennlist - Porsche Discussion Forums

Notices
997 GT2/GT3 Forum
Sponsored by:
Sponsored by: Porsche North Houston

Clutch on 997 GT2

 
Old 08-30-2013, 01:07 PM
  #31  
TB993tt
Addict
Rennlist Member

 
TB993tt's Avatar
 
Join Date: May 2001
Location: UK
Posts: 4,224
Default

Originally Posted by Kevin View Post
Toby, your LWFW better NOT make any noise. You have a solid centered clutch disk. That's a nasty clutch for street city driving. Parking on any sort of ramp, or parking garage would be a chore. With the large sprung centered disk my wife can drive the car. Can your wife back the car out of the garage with the solid centered disk?
She hasn't driven it since I had the new engine done, so just for you - first time and no stalls

TB993tt is online now  
Old 08-30-2013, 01:36 PM
  #32  
Kevin
Addict
Rennlist Member


Rennlist
Site Sponsor

 
Kevin's Avatar
 
Join Date: Jun 2001
Location: Northwest
Posts: 8,474
Default

Toby all smiles....
Kevin is offline  
Old 08-30-2013, 01:48 PM
  #33  
TB993tt
Addict
Rennlist Member

 
TB993tt's Avatar
 
Join Date: May 2001
Location: UK
Posts: 4,224
Default

Originally Posted by Kevin View Post
Toby all smiles....
Kev - seriously you should find out (I'm sure Thomas as CG will know or can find out) what exact set up I have because it seems it is the panacea for LWFW clutches which can:
1) hold real engine dyno braked 920NM
2) Be quiet enough for daily use
3) Be easy enough for a girl used to auto trans to drive.
TB993tt is online now  
Old 08-30-2013, 01:55 PM
  #34  
Kevin
Addict
Rennlist Member


Rennlist
Site Sponsor

 
Kevin's Avatar
 
Join Date: Jun 2001
Location: Northwest
Posts: 8,474
Default

Toby, if you can email me the number that would be great. I will be needing a new clutch in mine shortly..
Kevin is offline  
Old 08-30-2013, 02:06 PM
  #35  
F1CrazyDriver
Addict
Rennlist Member
 
F1CrazyDriver's Avatar
 
Join Date: Nov 2006
Location: SF Bay Area
Posts: 2,028
Default

^ Kevin knows his clutches/lwfw stuff. I had it installed on my 996t.

Chatter didn't bother me. Worked great for street and track. I'm not sure which one he sold me, i just told him my usage with car and my mods, simple. If i decide to upgrade the one on 997.1 i will be form Kevin.
F1CrazyDriver is offline  
Old 08-30-2013, 03:24 PM
  #36  
sideways_swe1
User
Thread Starter
 
Join Date: Feb 2011
Posts: 66
Default

chatter dont bother me either. Kinda like it actually! Reminds me that im not in an ordinary car
sideways_swe1 is offline  
Old 08-31-2013, 12:12 PM
  #37  
ILLCOMM
User
 
ILLCOMM's Avatar
 
Join Date: Nov 2012
Posts: 329
Default

Any reason to be concerned about harmonics when moving to a LWFW on a GT2? I heard this is what is causing cam bolts to back out on the GT3RS'
ILLCOMM is offline  
Old 08-31-2013, 01:32 PM
  #38  
Kevin
Addict
Rennlist Member


Rennlist
Site Sponsor

 
Kevin's Avatar
 
Join Date: Jun 2001
Location: Northwest
Posts: 8,474
Default

The LWFW has been install since the early 90's.. And run on this engine platform since. The GT2 does NOT turn the RPM's that the GT3RS does. With the two versions of LWFW available, I would recommend the early RS version that is slightly heavier. The LWFW clutch has been run for 10 years on the 996GT2 with no cam bolt backing off.
Kevin is offline  
Old 09-01-2013, 04:46 AM
  #39  
MGS996
User
 
MGS996's Avatar
 
Join Date: Jan 2006
Location: Melbourne, Australia
Posts: 298
Default

Originally Posted by sideways_swe1 View Post
Im not doing it for the sound. I kind of like my gt2 being a little quite compared to the gt3 with cargraphic race kit. Im wondering if i will "loose" power with stock exhaust with 100cell cats compared to a complete crosspipe exhaust for example. I know a more freeflowing exhaust is better when tuning more heavily. But with a tune only?
The OEM 997GT2 exhaust is made by Akrapovic – correct. But the non-EOM unit manufactured by Akrapovic has a more open and free flowing internal design. And for what it’s worth the Cargraphic supplied Cats are of unsound quality (in other words crap!)….I had them fitted for about one week before removing them and fitting a complete Akrapovic system (quality & fit is chalk & cheese).
Regarding clutch & flywheel kits, I installed a LWFW kit on my recently sold 996TT. Package was supplied by Kevin. Highly recommend the kit!
MGS996 is offline  
Old 10-13-2013, 02:17 AM
  #40  
TeCKis300
User
 
TeCKis300's Avatar
 
Join Date: Sep 2013
Posts: 136
Default

Kevin, what are your thoughts on the ERP setup (2 plate) for an all arounder, primarily street with a few track days a year?
TeCKis300 is offline  
Old 10-13-2013, 02:52 PM
  #41  
Kevin
Addict
Rennlist Member


Rennlist
Site Sponsor

 
Kevin's Avatar
 
Join Date: Jun 2001
Location: Northwest
Posts: 8,474
Default

TeCK I have not installed the ERP clutch. I have run Tilton's setup. For the street use both are a little overkill. I'd run the factory LWFW and 764 pressure plate for the street GT2 (drivers ed use)..
Kevin is offline  
Old 04-10-2014, 01:10 AM
  #42  
Edinsf
User
 
Join Date: Nov 2013
Posts: 243
Default

Originally Posted by TB993tt View Post
She hasn't driven it since I had the new engine done, so just for you - first time and no stalls

TB, I like the sound of your exhaust. Who makes it?
Thanks.
Edinsf is offline  
Old 04-11-2014, 01:49 PM
  #43  
TB993tt
Addict
Rennlist Member

 
TB993tt's Avatar
 
Join Date: May 2001
Location: UK
Posts: 4,224
Default

Originally Posted by Edinsf View Post
TB, I like the sound of your exhaust. Who makes it?
Thanks.
It is a Cargraphic 100 cell cat switchable exhaust which has been modified with perforated pipes and wire wool type stuffing in the mufflers see photo below (the solid straight through pipes proved a little noisy and tiring for long journeys)
THe car has higher capacity and cams so sounds a bit different to a standard engine.
TB993tt is online now  
Old 09-26-2014, 06:21 AM
  #44  
emmo.84
User
 
Join Date: Jun 2008
Posts: 24
Default

Originally Posted by Kevin View Post
Guys, to shed a little information on the Porsche clutches...

Everything is based off the flywheel. Once you have figured out your flywheel>> three factory choices. Then you can start to build your clutch kit..

The reason why we want to focus on the flywheel "is" it dictates which clutch disk one MUST use. For instance you cannot use the 996GT3 or997GT3 4.0 ltr or GT2RS clutch disk WITH a dual mass flywheel. You cannot install that disk in a 996GT2 or 997GT2. Guy have tried, and then on startup you find yourself not being able to get the car in gear of out of gear.. It is a common mistake.

I'm going to skip the clutch disk options for a moment and jump over to the pressure plates. There are 4 factory Sachs pressure plates that get tossed into the mix. Many internet and parts houses for the last 20 years have opted to insert the 964 NA pressure paired with the 964 RS lightweight flywheel. This has happened for years, on 993TT and 996TT. I still get emails and parts breakdowns with shops trying to install it on 997TT/GT2.. Flat out THAT NA pressure plate will not work. The plate will fail within the first week. I think that there is confusion between the 764 plate and the 964NA car when they look at the RS parts breakdown.

The 2nd plate is the Turbo pressure plate. The plate that leaves the factory 993TT, 996TT, 996GT2, 997TT, and 997GT2... Over the years part numbers have changed, but it is still the factory TURBO plate. It is a bullet proof plate but will NOT hold with a good tune. It is foolish to install this pressure plate when you can get two other factory pressure plates that do a better job.

The 3rd plate is a Sachs Race Motorsports plate with a part number that ends in 752.. This plate is a upgrade over the factory Turbo plate. It is great for the stock turbo 993TT, 996TT, 996GT2 and 997GT2RS.. With the normal bolt on mods this plate works well. BUT will not hold more aggressive tunes and track outings.

The 4th plate and best factory Sachs Race Motorsports plate ends in 764. Toby refers this as the 890Nm unit. It would be easier for newbies to call it the 764/890Nm plate. I can post the physical differences of this plate vs others in another post.. This is really the best choice for a replacement clutch, whether you keep the dual mass flywheel or not.

Warning>> Do not get caught up in the sales marketing STAGED kit numbers.. You can get hosed big time. For the Turbo and GT2/GT2RS owner, make sure you ASK which pressure plate you are getting.. Turbo, 752 or 764.... Call it the Stage Master blaster XYZ.. But in the end get the pressure plate that you want to fit your driving and power output. With that said, the 764 plate can and does fail. Drag strip runs, race track events, and extreme HP outputs will make short life of this plate.

The next topic area is the clutch disks. And over the years Sachs has modified the disks to keep up with better manufacturing and higher torque outputs.. I will make a few blanket statements to clear up some myths.

a) The factory 996GT2 disk is a solid centered NON sprung disk. It has a slight edge in torque rating vs the standard turbo disk (the turbo disk is sprung) the organic lining between the two disks are the same.

b) You cannot install a 996GT2 disk and/or 997GT2 disk with a factory lightweight flywheel. The reason is.. The flywheel is thicker>it is closer to the backwall of the transmission bellhousing. Be careful, standard turbo and GT2 disk can only be paired with the dual mass flywheel.

c) The BEST and strongest clutch disk for track use has been the 996GT3 and new improved 4.0 ltr disk. These disks are sprung to absorb the energy since the lightweight RS flywheel is in place. You cannot use these disk with the dual mass flywheel. They are to tall, and the sprung center doesn't clear the internal cavity between the dual mass and pressure plate. Sachs has redesigned the 997 4.0 disk with smaller diameter springs to reduce the rattle. I favor the 996GT3 disk since the organic lining is the same as the 4.0. The torque output rating is similar. The 4.0 with the new springs can handle more torque at extreme RPM's which our turbo engines don't see.

The last option from Sachs is 4 puck race (bronze) clutch disks. These coupled with the RS LWFW turn street driving into a nightmare. You have to rev the engine to 3500 to 4K to get the car moving. The reason for this disk is because the organic lining just isn't up to the task and heat in racing. One option prior to getting the 4 puck version is to use a aftermarket lining manufactured in Canada. It comes with a 6 puck or 8 puck glass lining and one removes the factory organic from either the Rigid GT2 disk or Preferred GT3 disks. This is the better choice for High Output street cars. Once you smoke these disks, you need to upgrade to twin disk and carbon multi disk systems. Such as Tilton units.

Lastly, like I mentioned in the beginning, the flywheels dictate the clutch choice. It is a flow chart, that has to be explained to your tuner. One clutch kit doesn't fit all the boxes. You could have a stock output 997GT2.. But you race it twice a week in DE or open events. If that is the case I would strongly recommend the RS lightweight flywheel with the 764/890Nm pressure plate and either the 996GT3 clutch disk or 4.0 clutch disk. For tuned engines, I would recommend the same. If the GT2 that gets track is tuned, one can recommend the 8 puck glass lining built on the GT3 disk.

My personal opinion, I don't recommend the factory dual mass when placed into service on the track. I think that the LWFW is better option. Modern tuning today will deal with the previous year stalls and low RPM bucking. The noise or rattle will still be there. But if you have a loud exhaust, who cares.. Shedding 18 lbs of weight pays in the long run. Find a fellow Rennlister to get some seat time in. Please note that many failed LWFW kit have been sold over the years. It is a failure to use any LWFW with a non sprung clutch disk. Many kits come with the GT2 clutch disk. It turns this kit into a nightmare light switch event.

There is a difference between the RS flywheels. The early CUP design is tweaked for production in the 997RS.. The ONLY difference is that it is roughly 2 lbs lighter vs the 964 RS flywheel. 9.2 lbs vs 10.5 to 11.0 lbs. What is different is>> the DME trigger ring is back cut. With the RS flywheel, you have finger for the DME trigger wheel (60 -2) versus solid teeth on the 964 unit. I recommend the 964 RS LWFW.

I have sold hundreds of these kits and no two owners are the same. If you hate the LWFW rattle, go with a dual mass kit. Make sure that you are getting the 764 pressure plate.. FYI, I sell the RS LWFW kit with the 996GT3 clutch disk and 764 pressure plate for $2,295.00 If you want the 4.0 disk it's $200 more.. Feel free to email or call me...
Hi Kevin,
great to find so much Porsche clutch knowledge in a guy! I agree on everything you wrote, plus I experimented all of the pressure plates, AND NOW I'M IN TEARS...
I have a 997 GT2 my2009, 100 cell + ECU modified by RS Tuning, (maybe 600 HP). I have single mass FW and parts.
STD Clutch set up: slip
Switched to single mass FW and parts, put new clutch parts.
752 + 996RS disk: OK, but now 752 out of production
764 + 996RS disk: too hard pedal in street use, bad, 'steplike' feeling on the pedal expec. when hot
(all fork command, bearings, shift, miscellaneous, new)
Ended up yesterday with a swap to RS4.0 plate + RS4.0 disk..... Much better pedal feeling, out on the highway for small test: it was already slipping in 5th and 6th Gear ... (!!!!!DESPERATE!!!)
Is there any braking in to be made or this clutch setup is wrong? THANKS A LOT.
emmo.84 is offline  
Old 09-26-2014, 06:30 AM
  #45  
emmo.84
User
 
Join Date: Jun 2008
Posts: 24
Default

Looking at the RS 4.0 pressure plate, it seemed reinforced vecause of the triple bands on the perimeter, plus they're bolted and not riveted, I understand the spring is lighter than a 764, and that's what I was looking for, but I can't uderstand the fact that a reinforced pressure plate and new RS 4.0 disk do not hold the torque and power of a 997 GT2...

Maybe they have to 'couple' themselves for perfect contact??
emmo.84 is offline  

Thread Tools
Search this Thread
Quick Reply: Clutch on 997 GT2


Contact Us About Us Advertising Cookie Policy Privacy Statement Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: