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Discussion Starter #1
I have the ACT XDSS right now, and, it's not so bad. I think what I really don't like is the lightweight flywheel.

I like how the engagement/dis-engagement is very predictable with the pedal. The OEM seemed to always 'float' around it's engagement point.

Anyways.. motor is out.

Main requirements - daily driver friendly clutch that has predictable pedal engagement ... and... can hold upwards of 550 torque.

If it's the XDSS ok. But, I'd like to hear what others like and dis-like too.
 

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550 wheel torque? or crank torque?

my exedy HD Organic stage 1 clutch is rated at 472 ft lbs at the wheel or 600 ctq. Its horrible to drive. its heavy as shit, it chatters bad and its difficult to slip it even a bit when in stop and go traffic. I am replacing it with a Southbend stage 3 daily here soon
 

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I cant speak from experience as I have an ACT 6 puck in my car, but I too am looking into upgrading a clutch to something that can handle high amounts of torque while hopefully being more user friendly. I was going to try out a twin disk, Im under the assumption that with 2 disk the peddle pressure decreases as the force is shared between two disk. Rather than my single disk clutch which requires more pressure in order to withstand the torque. Can someone agree with my logic or not?
 

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I have the ACT XDSS right now, and, it's not so bad. I think what I really don't like is the lightweight flywheel.

I like how the engagement/dis-engagement is very predictable with the pedal. The OEM seemed to always 'float' around it's engagement point.

Anyways.. motor is out.

Main requirements - daily driver friendly clutch that has predictable pedal engagement ... and... can hold upwards of 550 torque.

If it's the XDSS ok. But, I'd like to hear what others like and dis-like too.
The ACT XDSS is your best bet. It's the most stock like feel, albeit a tad stiffer and a tad lower engagement point, but very predictable. I love mine. It's been on for 2 years now, and 2 winters. Once broken in, it's super quiet and very easy to maneuver in traffic. I can easily ride the engagement point forever with minimal gas input. I couldn't be any happier with that part of my rebuild.

I didn't go with the lightweight flywheel. I've never experienced one but after reading so many reviews and comments. I decided I preferred the combination of a lightweight crank pulley and a one piece driveshaft instead since it's not recommend to have all three together on a street car.

I cant speak from experience as I have an ACT 6 puck in my car, but I too am looking into upgrading a clutch to something that can handle high amounts of torque while hopefully being more user friendly. I was going to try out a twin disk, Im under the assumption that with 2 disk the peddle pressure decreases as the force is shared between two disk. Rather than my single disk clutch which requires more pressure in order to withstand the torque. Can someone agree with my logic or not?
Do you actually "need" a clutch that can take 660 to 755 of torque?! 6 pucks aren't meant to be daily driven...
 

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Thanks Noximus - good info. Curious - have you driven a 6 puck? A lot of mixed reviews and half of them say they're very streetable, easy to slip, and not the on / off switch some say they are.

Light weight flywheel, pro-light, is the real problem here. It makes backing up in parking lots a pure pita, steep driveways, etc etc. I even tuned down my RT in that area so I could feather the gas a bit more but, in the end it's just not happening.

I can't say I'm going to miss the other benefits because they didn't stand out to me that much. It may be one of those 'don't what you got till it's gone' type deals though too!
 

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Thanks Noximus - good info. Curious - have you driven a 6 puck? A lot of mixed reviews and half of them say they're very streetable, easy to slip, and not the on / off switch some say they are.

Light weight flywheel, pro-light, is the real problem here. It makes backing up in parking lots a pure pita, steep driveways, etc etc. I even tuned down my RT in that area so I could feather the gas a bit more but, in the end it's just not happening.

I can't say I'm going to miss the other benefits because they didn't stand out to me that much. It may be one of those 'don't what you got till it's gone' type deals though too!


I have driven a 6 puck in a 08 STI. It’s why I didn’t go with one. I much prefer the feel of the XDSS on the street. It just feels perfect for me. Once broken in, I only notice the extra stiffness once in a while, but otherwise it feels like a natural STI clutch. I don’t drag or launch or track, and have stopped doing autox since my rebuild. The only comment I guess I could have is that it’s pretty stiff in the winter. You almost have no choice to let the car warm up 5mins on colder days.

I would almost try getting rid of the lightweight flywheel in your case. It’ll probably make you love the XDSS again.
 

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I didn't go with the lightweight flywheel. I've never experienced one but after reading so many reviews and comments. I decided I preferred the combination of a lightweight crank pulley and a one piece driveshaft instead since it's not recommend to have all three together on a street car.
Replying cause of the last line. DS has nothing to do with the rotating parts including and directly connected to your drive shaft, like your flywheel.

As for Lightweight flywheels, Fine for flat-landers. I could see avoiding one if you regularly have to stop and start on hills. I'm a flat-lander, so no real issue here, but a significant difference in rev speed.

Clutch? After two HDSS failures at 10K miles with no abuse what so ever, I'm running a Excedy Hyper single - the lightest rotating assembly I've ever ever run -by fay - light clutch and light fly-wheel. Feel - uh, I get a kick out of it. My son says it's ridiculous. For the first time I think I can tell I have a clutch delay valve that makes the rapid engagement difficult to judge. I'll eliminate it this summer.

Rating. Torque is very low. They must rate it differently from others. When I chose it, the shop sales person just said don't worry about it compared to the HDSS. So it's only rated at a bit over half what you are looking for. Discussing feel cause it is 6 puck and Excedy actually mention that it's fast engagement is intentional. It's a much smaller percentage of pedal travel than my HDss's were. They felt like a stiff stock clutch.

Added:I feel the short engagement actually does make shifting faster possible.
 

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Replying cause of the last line. DS has nothing to do with the rotating parts including and directly connected to your drive shaft, like your flywheel.

You’re saying a CF DS doesn’t reduce your rotational mass? Really?

There have been documented issues when using a CF DS, 12lbs lightweight flywheel, and a lightweight crank pulley. They have fixed it by going with a heavier lightweight flywheel, return to the OEM flywheel, return to the OEM crank pulley or to a Fluidampr crank pulley.
 

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If you drive around in neutral it might cause problems.. :D

You’re saying a CF DS doesn’t reduce your rotational mass? Really?

There have been documented issues when using a CF DS, 12lbs lightweight flywheel, and a lightweight crank pulley. They have fixed it by going with a heavier lightweight flywheel, return to the OEM flywheel, return to the OEM crank pulley or to a Fluidampr crank pulley.
 

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Do you actually "need" a clutch that can take 660 to 755 of torque?! 6 pucks aren't meant to be daily driven...

Do I "need" a Clutch that can take 660-755 of torque? Depends on how far i'm looking to push this 4 cylinder. Technically I dont "need" a clutch that high, or even "need" to own this car all together. I'm very aware that a 6 puck is not meant to be daily driven on, and I do believe I said my car was not a daily driver either so I am not worried about daily driving a 6 puck clutch.

From my understanding you dont have to have a twin disk that goes as high as you mentioned, sure they do but I do believe that exedy's and other brands offer lower holding torque capacity. I am hoping someone with real world twin disk experience can chime in about pedal pressure between a single disk traditional clutch and a twin disk kit designed to hold the same amount of torque?
 

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Do I "need" a Clutch that can take 660-755 of torque? Depends on how far i'm looking to push this 4 cylinder. Technically I dont "need" a clutch that high, or even "need" to own this car all together. I'm very aware that a 6 puck is not meant to be daily driven on, and I do believe I said my car was not a daily driver either so I am not worried about daily driving a 6 puck clutch.

From my understanding you dont have to have a twin disk that goes as high as you mentioned, sure they do but I do believe that exedy's and other brands offer lower holding torque capacity. I am hoping someone with real world twin disk experience can chime in about pedal pressure between a single disk traditional clutch and a twin disk kit designed to hold the same amount of torque?
I run a twin plate in my Porsche and while it'll hold plenty of power it's awful in traffic!

 

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Probably from the rev up and down while inching forward etc. It’s been a few years since I’ve done that research.
The driveshaft basically isn't doing anything in that situation. I'm not trying to argue with you at all. I was just trying to be funny. The flywheel/clutch revs with the motor. The DS does not. It just moves if the car moves so it's not going to have any effect on that issue. Just like lightweight wheels or brakes wouldn't either.
:tup:
 

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You’re saying a CF DS doesn’t reduce your rotational mass? Really?

There have been documented issues when using a CF DS, 12lbs lightweight flywheel, and a lightweight crank pulley. They have fixed it by going with a heavier lightweight flywheel, return to the OEM flywheel, return to the OEM crank pulley or to a Fluidampr crank pulley.

Error on my part, meant crank-shaft. Rotational mass meant of the engine, any sensors and the codes they might trigger.

ADDED: Sure I've read of cases where lightweight rotating assembly, (the parts that should be balanced together) created problems that were cured by swapping those parts - sometimes with heavier parts. Make me wonder how far you have to go, IE very lightweight rotating assembly, strong cam springs and large cams, and tune, or how poor a job you have to do overall to make that happen - cause I believe some people run all that and don't have problems. Anyway . .

the DS will not affect them.

Porshe parts are always so pretty! Need one just to have a reason to buy them! :)

NJ-Kiter? You doin the install?
 

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Thanks guys, If i were to not do a twin disk i would shoot for a full faced clutch as the 6 puck though is great for what its advertised for does not last as long as other kinds. Yes mheyman i would be doing the install myself.
 
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