Twin disc clutch experiencs!!!

[TurboSouthAfrican]

First off, I have been lurking here for a while and everyone seems more knowledgeable about the motor and working on their cars than most of the sites I visit.

 

I have a RB26 with RB25 tranny. I am need of a clutch that will support a ceiling of 600 HP, which would put torque around 500 or so. I like to hear from the guys running twin disc clutches or a single disc that support that much torque. I am not against spending money but I am on a budget, which is somewhat bust already. Thanks for the input guys.

 

Larry(THE NEWBIE)

[Hey_Allen]

While I don't know anything about the twin disk clutches personally, you might find a bit of information on the Subaru forums.

 

When I was driving a STI, there were a number of guys who were burning out the clutches on them, and one of the more common upgrades was to go to a multi disk setup. I had managed to fry my clutch, but was babying it along still when the car got totaled.

[triple B]

a twin disk clutch does not neccsasarily hold up to more torque. in theory a twin disk clutch is to provide more surface area in a smaller package so that the bite of the clutch stays the same as a larger unit.

a multidisk clutch will support more torque and lots of bite as there is a much larger surface area of friction material and the multiple plates will allow more slippage so that the clutch unit can handle the increase in torque while allowing the power to transfer to be unaffected.

 

 

the key thing is when you have lots of torque the clutch slips and burns up because it cannot handle the load being put on it. the best comparison i have heard is its the same affect as haveing a brake caliper frozen and it eats the pad 10 time faster. the friction and heat kill it and the material becomes glazed and ruined and the rotor itself ( or in this case the flywheel) become warped and ruined due to heat.

 

Exedy clutches are a multidisk design and hold up very well. our club president and race team leader has one in his EVO 8 which is around 716 hp to the wheels and just shy of 500 ft lbs of torque. extended repeated use ( like at the track) will give you slippage but thats just a fact of life for anything when lots of heat is involved, well except for carbon fiber stuff you have to get that stuff hot to have it work right

[TurboSouthAfrican]

a twin disk clutch does not neccsasarily hold up to more torque. in theory a twin disk clutch is to provide more surface area in a smaller package so that the bite of the clutch stays the same as a larger unit.

a multidisk clutch will support more torque and lots of bite as there is a much larger surface area of friction material and the multiple plates will allow more slippage so that the clutch unit can handle the increase in torque while allowing the power to transfer to be unaffected.

 

 

the key thing is when you have lots of torque the clutch slips and burns up because it cannot handle the load being put on it. the best comparison i have heard is its the same affect as haveing a brake caliper frozen and it eats the pad 10 time faster. the friction and heat kill it and the material becomes glazed and ruined and the rotor itself ( or in this case the flywheel) become warped and ruined due to heat.

 

Exedy clutches are a multidisk design and hold up very well. our club president and race team leader has one in his EVO 8 which is around 716 hp to the wheels and just shy of 500 ft lbs of torque. extended repeated use ( like at the track) will give you slippage but thats just a fact of life for anything when lots of heat is involved, well except for carbon fiber stuff you have to get that stuff hot to have it work right

 

The Exedy multidisk is what I was looking at, $2300 ouch!!! There has to be someone on this board who is running this type of combo, who has personal experience with some type of after market clutch for this motor, tranny combo, please chime in. I took out the clutch today, what a pain in the rear. I really see problems trying to get trans back in, the tilt angle was severe, when I finally slid the tranny off.

[Careless]

purchase booztd3's os giken setup that he's selling only because his sponsor has provided him with another clutch. it still has most of its life left into it, and survived many 700 rwhp launches.

 

none of which slipped, and the clutch was never the weakest link, causing various other things to go bonkers because it held up so well.

 

 

he's dropped the price considerably, and the unit is 2000 new, so give him a holler, or look for the thread, it was semi-recent.

 

[Stealth-Z]

purchase booztd3's os giken setup that he's selling only because his sponsor has provided him with another clutch. it still has most of its life left into it, and survived many 700 rwhp launches.

 

none of which slipped, and the clutch was never the weakest link, causing various other things to go bonkers because it held up so well.

 

 

he's dropped the price considerably, and the unit is 2000 new, so give him a holler, or look for the thread, it was semi-recent.

 

To late on the clutch. I remember seeing it up for bids on ebay.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=330175143528

[MONZTER]

I have been running a twin disc clutch master FX-600 for over a year now on the street and Autocross. It uses Kevlar on the disc so its not as grabby as the FX-700 that uses metal. I was having problems breaking the straps on a standard type clutch and the design of this unit eliminated that with the aluminum pressure plate. The complete unit including flywheel weighs 17 lbs. The speed at which it revs is insane. I have had no problems with it, mind you I dont have 500 HP but my new motor will be close to that and I plan on swapping it right over.

 

Jeff

 

 

[WizardBlack]

If you can get a single disk that will hold the power and still provide a sprung hub, go for it. If it's a puck clutch, it won't last as long; especially the fewer pucks there are. If it's still a full face disk; that's the way to go.

If you can only get a solid hub design, it's up to you. They can be hard to control. It depends on how good you are with the clutch and what you intend to use the car for.

Multidisk clutches will allow more slip for the same disk diameter. This lets it hold more torque because human beings usually reduce what torque the clutch will hold with their shifting and slipping.

I have driven multidisk cars before. They can have a stock or even lighter pedal feel and still hold a lot of power. That being the case, you really have to check the disk diameter, disk thickness and disk composition to determine how long they will last. They aren't as easy to determine how long they last without a lot of experience with them and checking the physical nature of the clutch.

I had an HKS twin-plate. It was nice, but a lighter flywheel and tough single disk works just as well IMHO. Not worth the money unless the car can only accept a fairly small diamter clutch (which I don't think is the case here) or you are building a no-budget 'race' car or need every last ounce of power holding. 600 shouldn't be that hard for a sprung hub on an RB motor.