I am looking at a new clutch, and in anticiaption of possibly doing some other mods, I plan to get a racing clutch, LWFW, and to do the conversion to the GT-2 style hydraulics.

My question is this: Do I also need to change the crank pulley when I go to a lighter weight flywheel? I've heard conflicting reports. Please enlighten me as to what you have done on your cars.

Thanks!

Jon

 

I did not.

UMW sachs clutch and lwfw good to 700hp per Kevin.

EVOMS gt2 kit.

Stock pulley (or it came in the kit from Kevin). That kit, btw, was plug and play and he helped my tech get around issues. Dropping the tranny saves hours btw...

My BOV's are from him too....did those way back at the same time.

Jeff

 

noone is changing the harmonic dampner. some cars need this ours seems to not. havent even seen one available for the car.

make sure you leave room to grow with the clutch and get one that will take your horsepower requirements now and down the road. so if you need a stage 2 clutch for what your doing now think about getting a stage 3 clutch to hold what you do to the car later.

William

 

Thanks, Jeff,

This looks like the route I am going to go as well. My tech drives a GT3, and for that engine the crank pulley seems to be important. Maybe because they rev so much higher than ours?

Jon

 

Some GT3 owners who did a conversion to the LWFW (a la GT3 RS) experienced problems that Porsche ultimately refused to cover.

Technical Information
Service
36/08 ENU 1360 1
GT3 Engine: Flywheel and Pulley
Vehicle Type: 911 GT3 (997)
Model Year: As of 2007
Concerns: Flywheel and pulley
Information: Replacing dual-mass flywheel with single-mass flywheel.
We have discovered that the dual-mass flywheel, which is installed as standard in the GT3 engine (vehicle type 997810/-811), is being replaced in the dealer organization with the single-mass flywheel from the GT3 RS engine (vehicle type 997850/-851).

Information

Due to an increasing number of reported faults, we expressly wish to point out that the installation of the single-mass flywheel (from the GT3 RS) in the GT3 engine is not approved by Porsche.

Since the 911 GT3 (997) engine application is designed for the dual-mass flywheel, conversion to the single-mass flywheel results in the following problems and consequences:

• The single-mass flywheel causes fluctuations and vibration in the lower rpm range, thereby reducing the smooth-running performance of the engine.

• The crankshaft is subjected to one-sided loading, causing stress peaks that can result in damage to the crankshaft.

• The one-sided loading of the crankshaft can cause the pulley to come loose, resulting in damage to the belt drive and engine.

• Any damage relating to conversion or damage that can be attributed to conversion is not covered under warranty.

Please advise your customers of this information accordingly.

©Porsche Cars North America, Inc.

October 15, 2008

 

So is there a difference in the gt3rs and gt3 engine that makes the lwfw work?

 

the steel flywheel used in the 996TT clutch kits is from a 964RS, the other ones are custom units made for the 996TT.

 

Thanks to everyone for the clarifications. Got a little more research to do before I pull the trigger on the winter mods...

Jon

 

How does this not apply to the TT?

 

I did the oem RS pully when I installed my Aasco lwfw...I believe these are the PN's for what you'd need:

996 102 017 95 RS Crank Pulley
999 217 128 08 Pulley Bolt
999 025 174 02 Spacer Washer

I'd have to double check but I believe the shorter belt you'll need is from the GT3...

 

Kevin and I talked about the LWFW and his feeling at the time, 25,000 miles ago ....was that it loaded the bearings in the engine "less"... Given that he builds engines.... So it would help protect the engine in his opinion and perhaps put less strain on things. I defer to him on this level of sophistication.

Clearly the unit works fine in the gt3rs.....

Anyway, I have had no issues. My unit is one of the 964RS units...whole thing is from Kevin at UMW. Perhaps it is wisest to get it all from one place from a person that is expert/builds the engine. Not saying you have to use UMW...just be careful to find a source that is expert. I chose him for my own reasons and have been happy. Other tuners have done other things on the car: the Switzer exhaust....he would be a good source of info too....Dan at Vivid for my suspension package.....no issues there so far.

The car is used every day. I see over 6000 rpm when the car is warmed up. No issues.
Boy does it rev fast!

Jeff

 

All of my customers that have gone with the Clutch Masters Stage 3 and LWFW have not had to change ANY parts as they are a direct OEM replacement.

 

Just as an FYI I did not change the pulley b/c the LWFW (aasoc) or clutch (spec) were not a direct fit with the stock pulley.

 

I have a Clutchmasters setup with a factory RSR LWFW and did not change any pulleys.

 

Same here... I didn't change the crank pulley at all...

Mike