Johnb55

I did an EVOMS ECU flash on my recently acquired 997 GT2 and definately feel the added power. The problem is, so does the clutch! In 4th, full throttle around 4,000 RPM it can't hold it and slips pretty badly. It holds in 2nd & 3rd, but gives it up in 4th. The car was CPO'ed with 7,500 miles when I got it. It has 8,500 now, and I have not used Launch Control. I understand that the clutch in the 997 GT2 is at it's limits in this application and others have experienced the same slipping after an ECU flash. The question is now what?

I've looked at clutch kits from EVOMS and AWE. Both have kits they say will handle the additional HP (up to 750 or 850). Both offer pressure plate and disk packages that retain the stock dual mass flywheel (28 lbs), as well as kits that replace the stock flywheel with a lightweight aluminum flywheel (11 lbs). EVOMS cautions that the lightweight flywheel creates a rattle sound in the cabin at idle and transmits more gear noise that is typically absorbed by the OEM dual mass flywheel. I love the idea of reducing rotating mass by 17 lbs, but do use my GT2 as my daily driver and don't want it to be rattly sounding. I actually kind of like a little gear noise, but I hate rattles.

What is the boards experience on this issue?

EVOMS or AWE?

Retain the OEM dual mass flywheel or go with the lightweight aluminum for a daily driver / occasional Track day car?

What clutch / Flywheel is on a 620 hp GT2RS?

Nick Wong

Single mass flywheel noise is like a Ducati dry clutch rattle. If you don't like the Ducati rattle, stay away from the single mass. I've had a Aasco single mass flywheel and Sachs clutch with four puck unsprung hub, and swapped it out for a full ERP/RPS triple plate carbon clutch which also has a lightweight single mass flywheel. The rattles don't bother me, I've got cars with transmissions that rattle far worse. You may not want to deal with that though.

TB993tt

First of all rating clutches by hp is a curiously US tuner thing, Sachs and most others rate them correctly in torque capability. The stock GT2 clutch is right at its torque limit with the car's standard torque output and on a cooler day the 700+NM can slip a stock clutch, mine and a few others experienced this.

If you do a search (or have a look at the fvd site which shows various options) you will find the Sachs clutches rated by torque and the 890NM set up will hold most tuned packages (unless they have a very abrupt torque delivery) and feel pretty much like stock to use.

I would go with the single mass flywheel, I wouldn't call it a rattle it is more mechanical and business like, makes the engine nicely responsive

bhgt2

I have a Switzer tune and my clutch started slipping immediately. I upgraded to Sach 2.5 and am very happy with it.

Sladep

John, I have basically the same set-up on my 997 GT2 and the same clutch slipping now. What clutch did you end up going with and how has it done? Can't moments on engagement point, smoothness, and resistance compared to stock would be appreciated. Would also like to talk to you about your EVOMS tune. Mine has a rough transition when going from say 1/4 or 1/3 throttle to closed throttle - kind of a slam instead of a normal transition. A call with you would be great. Let me know.

Slade

Johnb55;10404819]I did an EVOMS ECU flash on my recently acquired 997 GT2 and definately feel the added power. The problem is, so does the clutch! In 4th, full throttle around 4,000 RPM it can't hold it and slips pretty badly. It holds in 2nd & 3rd, but gives it up in 4th. The car was CPO'ed with 7,500 miles when I got it. It has 8,500 now, and I have not used Launch Control. I understand that the clutch in the 997 GT2 is at it's limits in this application and others have experienced the same slipping after an ECU flash. The question is now what?

I've looked at clutch kits from EVOMS and AWE. Both have kits they say will handle the additional HP (up to 750 or 850). Both offer pressure plate and disk packages that retain the stock dual mass flywheel (28 lbs), as well as kits that replace the stock flywheel with a lightweight aluminum flywheel (11 lbs). EVOMS cautions that the lightweight flywheel creates a rattle sound in the cabin at idle and transmits more gear noise that is typically absorbed by the OEM dual mass flywheel. I love the idea of reducing rotating mass by 17 lbs, but do use my GT2 as my daily driver and don't want it to be rattly sounding. I actually kind of like a little gear noise, but I hate rattles.

What is the boards experience on this issue?

EVOMS or AWE?

Retain the OEM dual mass flywheel or go with the lightweight aluminum for a daily driver / occasional Track day car?

What clutch / Flywheel is on a 620 hp GT2RS?[/QUOTE]

powdrhound

Get a 997GT2RS flywheel with 997GT2RS 4.0 clutch disc and a Sachs 487 Motorsport pressure plate. The 487 PP is basically a beefed up 997GT3RS PP. Drives like stock, holds 720 ft lbs of torque, significantly more than the stock PP. I ran this for a number years with success.

Johnb55

Slade, I got the setup as Powderhound described above and it's been great for 7 years!. There is no slip and smooth engagement. The pedal is a bit heavy, but I don't mind that. Also, I like the slight gear rattle at idle of the single mass flywheel. Both things remind me of what I'm driving. My EVOMS tune has been good, no rough transitions, and 617 rwhp on a cold spring day! Feel free to call me - c 732 618 0766