Double plate clutches

[spoolin70]

Today's question starts with the letter C.

Clutches or more specifically double/twin plate clutches. With the sale of Tronds Rev6 yesterday, it got me wondering. Are there any other twin or multi plate clutches available ? I believe Kennedy make one but I've never heard of one being used.

Japanese engines such as RB or 2JZ have a few available from HKS, Cusco etc. has anyone adapted one of these.

Just to be clear - I've got nothing against the Rev6, sure it's a great product, my inquisitive mind just wonders if there's another way 

Happy Friday everyone
Darren 

[Erlend / bug66]

Tilton has a 7,25" setup that could work..

http://tiltonracing.com/product/7-25-ot-ii-cerametallic-racing-clutches/

[Airspeed]

I've used both examples mentioned: Kennedy's and the Tilton (custom) solution.
Both work.

Kennedy's parts are a bit heavy, Tilton's rotating mass is super light, and/but more suited for fast shifting. It withstood my dragrace starts surpisingly well though, considering how thin the disks are.
Both Kennedy and Tilton disks made my flywheel and pp blue and black. The Kennedy pressure plate warped somewhat as most everyone will have experienced.

Thats where the Rev6 shines imo: the (single) plate is very thick and the whole concept is orientated to survive drag race starts longer.

[wph]

Assuming drag race application...

Hydraulic clutch user can set up the brake line going through a line lock solenoid and a bypass around it with a flow control valve.
When in first gear, the solenoid would be activated with a micro switch and force the fluid through the bypass and the flow control
can be adjusted to a soft clutch release. Friction components are to be treated as consumables...

http://magnusmotorsports.com/products/clutch-products-services/launch-control-device/

Parts for CMS cost less than 200 euros, rest of the clutch system needs to be chosen per horsepower and torque,
thicker discs and floaters preferred to tolerate more heat. Personally I'm going towards Tilton 7,25" clutch.
Single disc for N/A, double for forced induction.
 

[BeetleBug]

Stage 4 and black magic disc in combination with a hydraulic system and flow controlled return here. Best 60ft with MH Dot 215 tires and heavy street car is 1.448. Turbo engine. You need REALLY high HP numbers before you actually need a double/triple clutch system.

I had to search for a while to find a needle valve that actually worked. The commonly used ones does not give you a big enough window for adjustment.

-BB-

[Fiatdude]

I had a tilton setup and could NOT get discs for it -- they had stopped making VW spline discs -- and found a few people with some new/old discs but they would not sell -- but this was a few years ago

I had a clutch masters 3 disc and again they had stopped making VW splined discs -- no demand

I've got the Kennedy and I really like it for my autocross application -- I'm making 300 - 325 HP in my turbo application so it has a bunch of torque -- I would not recommend it in a application where you are needing to slip the clutch because it does not like to slip -- -- it will when I'm driving around on the streets and leaving stop signs etc., but it doesn't like it -- in fact there is one intersection here in town where I'm on a uphill incline and I've given up trying to slip the clutch when the light turns green, I just rev it a little and side step the clutch and let the tires to the "slipping" LOL

Mine is the dual disc with a stage 1 PP -- -- I find it to be a ton better in all ways over the stage 3 and a puck that I had in the Fiat and I'm still using the clutch cable and the pedal pressure (or actually the lack of it) is great

[spoolin70]

Some good and informative answers guys - thanks

Ok, can we narrow it down a bit. Flow control and solenoids (wph & Beetlebug) sound great (I used a stage 3 on the street and wouldn't hesitate to use one again, didn't find it too heavy personally) but I don't think it's going to apply to me/my car. It will see some strip use but mainly street with a bit of track day/hill climb in the mix. This is why I'm leaning towards double disc.

Walter - you mention custom tilton. How much work to get it to fit ? I'm using an adaptor plate already (non vw gearbox) so have a bit of extra room already.

Fiatdude - sounds like a good setup. For arguments sake, how do you think it would cope with double your horsepower ?

I guess the perfect scenario is soft pedal but high pressure and long life - seems to have one you must trade off the other 

Thanks
Darren

[wph]

I had a tilton setup and could NOT get discs for it -- they had stopped making VW spline discs -- and found a few people with some new/old discs but they would not sell -- but this was a few years ago

Aircooled Volkswagens are a niche market for clutch manufacturers, I don't expect to find anything off the shelf.
My goal is to achieve lowest possible clutch plate inertia for quick gearshift and controlled slip to protect/save the drivetrain.
I like the adjustability of Tilton clutches, several different diaphgram springs are available for different torque levels.
I was considering smaller than 7.25" diameter clutch but the price goes up and heat will become a problem with ultra thin discs.
 

     

[Airspeed]

You have to have/find a machinist that makes it fit on your flywheel. There isn't an off-the shelf part for it...



They are purdy parts though and not too costly. I use a G50 gearbox which has mendeola spline, so there is plenty out there on porsche items for it ;-)

[wph]

8)You have to have/find a machinist that makes it fit on your flywheel. There isn't an off-the shelf part for it...
They are purdy parts though and not too costly. I use a G50 gearbox which has mendeola spline, so there is plenty out there on porsche items for it ;-)

Very nice !  That pretty much sums up what I'm aiming to do

[Fiatdude]

Fiatdude - sounds like a good setup. For arguments sake, how do you think it would cope with double your horsepower ?

I'm at 350 HP right now -- if you need more grip go to a stage 2 PP

[Fiatdude]

Kennedy dual disc with 2 years of duty -- street/strip