Help me pick a clutch/flywheel

[crackership]

Hi All,

I find myself in a rather unique position (for me) where I have the entire drivetrain out of my 951 and I need to make a decision on what to do about the clutch and flywheel while I have it out. Here are the facts:

1. It makes good power. Hacky calculations based on logs from the VEMS tells me it makes about 425hp (will confirm on an actual dyno when it's all back together.)

2. I want to drive it on the street, in traffic and I don't want to regret my clutch and flywheel choice in those cases.

3. I would really like to no break clutch forks or crack the firewall.

After a lot of research, I landed on the Spec Stage 3 Hybrid clutch and pressure plate kit with the Spec aluminum flywheel (5.75lbs). But, even after all that research, I'm second guessing myself.

Experience with that clutch/pressure plate?

Alternatives?

Thanks in advance!!

[gruhsy]

I have that setup but with the metallic disk.
It easily held 450ft/lbs of torque.
It is however a heavier pedal.

I also have a kep1 and 930 disk.

Also the Sachs setup from Zims with a cup disc.

I would try the Kep1 with 930 disc or cup disc to have a nice pedal feel.

I should easily hold that power.

[crackership]

I have that setup but with the metallic disk.
It easily held 450ft/lbs of torque.
It is however a heavier pedal.

I also have a kep1 and 930 disk.

Also the Sachs setup from Zims with a cup disc.

I would try the Kep1 with 930 disc or cup disc to have a nice pedal feel.

I should easily hold that power.

thanks for the response! I have heard mixed reports on the Kep1 - some folks have told me they're a shurefire way to break your clutch fork - I take it you haven't had that issue though?

Did you have the light flywheel too?

[gruhsy]

I believe the Kep2 is the stiff pressure plate

Kep1 is similar to stock

Yes I have a Fidanza flywheel and 3 stock flywheels

[crackership]

I believe the Kep2 is the stiff pressure plate

Kep1 is similar to stock

Yes I have a Fidanza flywheel and 3 stock flywheels

.. are you selling any of them?

[Tom]

I'm a broken record on this subject, but tried a number of clutch and PP combos on my car and the KEP1 PP with 951 cup disk (or 930 disk) is head and shoulders above the rest. It's the only combo I tried that has factory smooth engagement, while still holding 500+hp. Everything else shuddered or jerked to some extent. Lots if different Spec disks, but the ones I tried were by far the worst in terms of engagement. Made the car no fun to drive around town.

The KEP1 is a stiffer pressure plate, but the pedal pressure isn't beyond the range of normal. The bone-stock clutch on my old 1985 911 was stiffer and harder to modulate. Knock on wood, but no cracked firewall or fork here. I think that's mostly KEP2 stuff. Personally I wouldn't even consider another combo -- it can't get any better...

[crackership]

I'm a broken record on this subject, but tried a number of clutch and PP combos on my car and the KEP1 PP with 951 cup disk (or 930 disk) is head and shoulders above the rest. It's the only combo I tried that has factory smooth engagement, while still holding 500+hp. Everything else shuddered or jerked to some extent. Lots if different Spec disks, but the ones I tried were by far the worst in terms of engagement. Made the car no fun to drive around town.

The KEP1 is a stiffer pressure plate, but the pedal pressure isn't beyond the range of normal. The bone-stock clutch on my old 1985 911 was stiffer and harder to modulate. Knock on wood, but no cracked firewall or fork here. I think that's mostly KEP2 stuff. Personally I wouldn't even consider another combo -- it can't get any better...

Thanks Tom! Now the trick is finding a Kep Stage 1! Any ideas?

[gruhsy]

I believe the Kep2 is the stiff pressure plate

Kep1 is similar to stock

Yes I have a Fidanza flywheel and 3 stock flywheels

.. are you selling any of them?

No. Have 3 cars now

[Tom]

I'm a broken record on this subject, but tried a number of clutch and PP combos on my car and the KEP1 PP with 951 cup disk (or 930 disk) is head and shoulders above the rest. It's the only combo I tried that has factory smooth engagement, while still holding 500+hp. Everything else shuddered or jerked to some extent. Lots if different Spec disks, but the ones I tried were by far the worst in terms of engagement. Made the car no fun to drive around town.

The KEP1 is a stiffer pressure plate, but the pedal pressure isn't beyond the range of normal. The bone-stock clutch on my old 1985 911 was stiffer and harder to modulate. Knock on wood, but no cracked firewall or fork here. I think that's mostly KEP2 stuff. Personally I wouldn't even consider another combo -- it can't get any better...

Thanks Tom! Now the trick is finding a Kep Stage 1! Any ideas?

Just give them a call and they'll take care of you.

https://www.kennedyeng.com/clutches

[four0four]

I've got a KEP 1 and cup disk installed, can confirm it feels smooth and easy. No clue has to how much power I'm actually putting through it, (65-70% duty cycle on the 80 lb deka injectors at 18psi, so >300), but not nearly as much as you'll make.

As far as flywheels though - I emailed TTV recently after their 60-2 flywheel. It's in stock, and not expensive (<$450 to the US). It's not much lighter (7kg) than stock, but it makes setting up camsync a breeze in VEMS (without faffing about with auditrigger camsync masking - the 944 pnp VEMS requires hardware modifications for this). Currently weighing both options myself, so no actual experience either way

...I have to feel like a flywheel fully 1/3rd the weight of stock might be a bit troublesome in traffic.