what are the options and which stands the best chance of holding some decent torque from a 2.5 that does 60+miles a day.

I have seen some uprated covers with three springs , while others just run the two like standard. are there any option on materials in the centre disc?.

my own feeling is that for this sort of power , a paddle would be best but due to the road mileage it may not be the ideal solution to live with, unless someone knows of a fairly friendly one.

I know that threads like this have been covered before but opinions change and new products are released.

does anyone have any links, that gives ratings for standard and heavy duty covers/kits?

I've emailed Exedy/Daikin and will post their reply.

AP/BRD are working on something and will get back to me.

with a sport "push" actuator on a 5speed box, you can fit a Quartermaster multiplate organic clutch, also needs custom flywheel and extra friggin about.

Exedy hyper single or double, but still paddle and not that easy.

Plenty of evo owners use an Alcon 6 paddle clutch no problem (sprung centre).

Trouble is everything is being 'worked on' but by the time they have come up with something you've sorted it yourself.

Paul

T, don't even dream about using a paddle clutch as a daily driver, it will kill you even if it has a sprung centre plate.
I drove my hill climb 911 with one for 2 years, put a stock clutch back in and went faster.....
Graham.

cheers guys.

the clutch that is in has held surprisingly well , for what some suspect to be a standard "selected" cover. it has not given any indication of slip but has only been in for approx 2500miles(it was in another car with 440bhp/380lbf-ft for about 1000miles, in summer but slipped on launches) . the roads are cold,wet and slippy up here and I have this feeling that come warmer,dry weather , when the tar and tyres grip better , it will slip during normal use :( . if the car was running about 350/330 then it would be worth risking but the aim is eventually 450/400.

given that we are about to fit a 6speed box to the car, I would just like to try and lessen the chance of a failure in a few months, if there is something more suitable available. we manage fine swapping 5speed boxes about with the space and tools we have but I do not really fancy doing battle with a 6speed on a regular basis. not sure my knees,arms and chest will like acting as a transmission lifter with it :rolleyes:

I was sure I had been told of an uprated organic , with a triple leaf spring to increase clamping force further. I think it may have been an AP or helix but not the normal spec.

I have also been offered an exedy hyper to try and could fit this with a spare 5speed box we have, to see how it works while waiting for the 6speed to arrive. all that would be needed is to drive a few miles in town with it to see how snappy it is. anyone got any experience of them?


[Edited by T-uk - 12/27/2003 4:05:32 PM]

Just some thoughts:

Just fitted a 'stock' AP organic clutch. My stock STi V3 unit was just starting to slip @ 314 bhp on drag starts when hill climbing on sticky Kumho tyres (5000rpm + dump the clutch)
The AP unit feels so light I was sure I hadn't engaged the clutch relaese fork!It was made with the very same steel pressed cover plate as the STi's, same identification marks!
My friend has an RA with 348 bhp and 8.5'' wide hill climb slicks and he can spin the wheels with the AP organic.
A fellow competitor in a 480 bhp EVO5 uses a HKS 3 plate paddle clutch to good effect, the car ate Helix and AP units inside of a 1000 miles....and a flywheel each time!
Graham.

T-UK..

with the 6 speed.. replace the bottom studs for bolts..

and it might be an idea to file the holes a little where the locating dowels are.. (just slightly)

if you think you want to remove the 6spd reguarly then your mad.. they arent light.

thanks david,

good tip about the bottom studs. got a hi-lift trolley jack coming and might make up some sort of cradle to hold the box, so with the studs out the way we might get the box balanced on it and positioned easier.

do you have a paddle clutch in yours,what is it like around town?

I do not want to swap any clutch regularly let alone one with a 6speed box:(. personally I would prefer to fit something snappy but with a sprung centre to try and help with drivetrain shocks , rather than risk something light. I do not mind changing a clutch that has worn out through abuse but if it comes a regular thing because jb wont throw something heavier in , he can prescribe himself some steroids and do the fcukers himself:rolleyes:. with a goal of 450/400 why play about trying for a refind motor , he should have bought an M5 for that.

Lateral organic cover is not standard, nor is the "sti" one which is the same as the AP one. Sti clamping force is 1050kg I think, Lateral is claimed 1500kg.

Daiken do make the cover pressings for Borg and beck, AP, Sti, Std, Daiken, Exedy, Greddy, PAR (lateral) and the list goes on.

Daiken = Exedy and also make many of the multplate clutches from jap tuners.

Organic will slip on harshe launches cause it can't deal with the heat like cerametalic or sintered. Increase plate pressure will help, but once too much heat is in clutch and flywheel your screwed and just have to wait, clutch fade if you will.

The STI item from the 6 speed is supposed to be pretty good as is.

What do you mean by 3 springs? There is one, the diaphragm.

Paul

Pavlo

It's the pressure plates you see all round the outer face of the clutch cover.
Most covers have two of these pressure plates, one on top of the other spread evenly around the cover. AP has 3.

Alan :cool:

launch's are not really the issue for this car. it will do the odd 1/4 but if the clutch was to heat up , the owner would probably just call it a day and not be too bothered.

paul, do you have any links on the PAR clutches?, if they are the lateral ones. I had a look on PAR's own site but could not find any clutch info. in scoobyshop , as you say , the lateral has a claimed higher clamping pressure but I recall a thread where andy measured everything and found it identical to a standard (STI-can't remember??) cover.

thanks alan, I was calling them leaf springs. can you share any rating differences , between the standard AP cover and this heavy duty one?.

Sorry John, never looked into specs much when i bought the clutch.

At the time it was a distress purchase as the original had failed, so took the decision to replace all parts at the one time.
AP with its reputation sold it for me plus i didn't have torque at that time which exceeded their recommended rating.

I think now though judging by feedback from heavier clutch users than me, that i would keep the cover i have just now and just replace the plate, rather than the whole hog

Alan :cool:

FWIW I can't detect any difference in pedal feel (weight) either between the AP cover (3 plate) and standard ( 2 plate) covers on other cars i've driven.

Alan :cool:

TUK.. I just balanced my box on the jack..


sit the box on the back of the jack so you dont need to be superman to alter the angle..

I positioned the box with my foot whilst bolting it up.. took no more than 20mins on my own.. (engine wasnt in)

I dont recommend putting the box on top of

a) a cheap jack
b) on your own

also make sure that you have the car high enough..
Std axlestands with my erm industial jack are about 4" too low..

Good luck.. its not that hard :D

Yeah Ive got a lateral paddle clutch.. I thought it was really bad, but then after a bit of use.. its not bad.. Car is in the garage awaiting some propane (its too cold for me to replace the back brake pipes (mot fail)) so I turned it around so I could prep the boot lid.. having driven dads 307hdi and then mine using a bit of revs with mine, it felt fine.. better than ever infact.. :confused:

If this clutch and gearbox can cope with me and my abuse then it will be perfect for you scottish girls :p (wonders what he's saying as the southerner jokes could apply to me now :()

David

Edited as I really didnt need my name twice :rolleyes:

[Edited by David_Wallis - 12/28/2003 12:21:35 PM]

Just buy a Draper gearbox jack. Cost about £80 which equals about two visits to the Osteopath..
Bit like a large scissor jack with a large shallow V top plate with strap, and the whole thing is on 4 casters.
Right about the height though. Went to the recent Prodrive sale and bought.....4 tall axle stands for £15.

This way the box comes out and back in on your own, saves buying all that beer for the mechanics!
Graham.

I don't think those leaf springs contribute much in the overall scheme of things when compared to the main diaphragm spring.

I don't have any links to PAR, all I know is I've seen the covers new and the pressure plate was different to a standard one. I am not sure if they increase the preload with a similar spring or what. The paddle is different to the organic for sure, set for different plate thickness'.

Personally, if you have a PAR cover, then I would investigate the thickness of the Alcon 6 paddle plate, as this is about £120 with sprung centre, and quite low on judder. Otherwise just keep throwing std plates at it if and when they start to slip.

Is this the "only one piece of talked up bollox left on any of the cars I work on." ?

Paul

paul,

that comment was probably a bit harsh to be honest , as the clutch has been okay so far. it is just with all the other issues in the past and with what andy had posted , I felt it was not worth the risk ***if*** it was just a standard cover , since the box was off and we could throw something heavier in , to "cover our ar5e" so to speak.

when I get chance I will remove the cover and compare it with a late standard one that I have here and will see if I can spot the differences you noticed, myself.

We don't want to be changing the clutch soon after the six speed goes in when the weather and traction improves. I don't want something I can't accurately parallel park in the tightest spots (obvious requirement of my job and using the car 70 miles a day in mixed traffic with visits to people's houses). I want it to hold 400 lbft easily.

As far as I am aware that means it has to be organic to give good manners. People that say you can drive a dogbox daily are driving gods and deaf, I am neither. Some realism is needed here, otherwise the BMW or Porsche showrooms will beckon and I will be remortgaging....

I am concerned that my present clutch whilst claimed good for 450 lbft will not be up to the job because of the appearances being identical to the standard clutch and disappointment with multiple aftermarket tuning parts that don't live up to their wildly optimistic ratings by any stretch of the imagination, although as pointed out above the clutches can be different but look the same.

Has anyone actually run 400+ lbft through an organic clutch on a Subaru for more than a quick test? (a quick test is not going to be a useful test to validate it to 400 lbft for 70 miles a day as far as I am concerned). I don't want to test something, I want something that works. Cash waiting to spare future hassle and more messing about.

I would be more than delighted if someone could back up with independent evidence the 1400kg clamping force rating on my present clutch as then I can just keep it and rest easy and get on with enjoying my car for more than five minutes before the next thing breaks. If they are individually tested to confirm the clamping force then there should be data?

[Edited by john banks - 12/28/2003 8:12:45 PM]

It should hold it easily, the problem is going to be heat. If that isn't going to be an issue for you John, I wouldn't worry.

Plate is nothing special from what I could see.

Bottom line is if you abuse (ie get really hot) the clutch, it will only be 50% better than any other abused clutch.

Sti clamping force is 1050kg - 1100kg I think, based on some US site selling said units. AP unit is same as STI AFAIK, so figure 40% more friction than those units when cool for the PAR stuff.

Twin plate exedy unit is £1200 or so.

Paul

I don't think heat or abuse are issues. My original UK clutch lasted over 30000 miles with up to 90% of my present torque at the end (the gearbox lasted 30000 miles and failed at 80% of present torque), and only slipped when the revs were too high on a few launches. In road use which is 99.9% of my car's use I can't see it getting hot, it just needs to hold what is actually not very much torque at all - just 400lbft - for long enough to reach a speed at which I have completed a short burst of acceleration. I am actually overly mechanically sympathetic so that it is at the expense of quite a lot of performance otherwise I would have broken a lot more parts!

[Edited by john banks - 12/28/2003 8:42:34 PM]

John

Have you looked here ?

http://www.3sxperformance.com/wrx/clutch.asp
Rated at 470lb-ft, sprung centre, kevlar plate and cheaper than your current unit !

From the Daiken catalogue the uprated pressure plate you have is +44% clamping force and rated at 2300lbs.
http://www.daikin-clutch.com/catalog...TS%20APP-3.pdf


Interestingly the Sti clutch cover part No ST3021055010 is rated at 2325lbs !!
http://www.subaruparts.com/catalog/?section=407

Andy




[Edited by Andy.F - 12/28/2003 10:56:48 PM]

Just like to piont out that the clutches I supply have nothing to do with PAR.

Also, IIRC, Andy posted that whilst he did get some slip on heavy launches, when removed, he found that the clutch hadn't bedded in yet.

The covers are NOT standard Exedy/Daikin, and do have increased clamping pressure.

There are limitations on how much you can increase the clamping pressure by, because it gets to the point where the lugs on the release bearing will just bend.

Mark.

Another possible area of confusion is that different suppliers rate their clutches in different ways.
There is the dynamic torque capability ie how much torque the clutch can transmit during slip. Then there is the breakaway torque rating ie the max torque the clutch can hold when fully engaged.
AP racing use the former dynamic rating, the breakaway torque figure can be considerably (+30%) higher but arguably of less significance regards launching capability.

Andy

I would be more than delighted if someone could back up with independent evidence the 1400kg clamping force rating on my present clutch

I would agree with that.

From the Daiken catalogue the uprated pressure plate you have is +44% clamping force and rated at 2300lbs

andy, this cannot be jb's clutch as his has a clamping force of 1400kg(approx 3086lbs)

good info from those sites

cheers

I've heard the lateral performance clutch is ace...but what's it like to live with? Heavy? Would it last 450/400 with 6 speed and relatively easy driving...I don't push the car much, as I like me licence!!

for any computer folk who can find out info from numbers.

removed the clutch.

Daikin
centre disc 2K08
cover 2K16
diaphragm 000
548
2K03

[Edited by T-uk - 12/29/2003 4:43:29 PM]

Clutch is fine to live with - like standard without the judder - I would love to keep it if I was convinced it will not slip.

The flywheel is blued (more in 2000-3000 miles than the original was in 30000) suggesting a fair bit of heat (I'll get some pictures), which is surprising given it is a new billet flywheel and has only done 3 weeks of road mileage and about four launches in total. I didn't notice the clutch slipping in use. But whilst we have the box out I want to get it right. The clutch plate looks fine. What is going on then?

Do I just pop this clutch back in given the 1400kg clamping force?

I run a L/P clutch and flywheel in my STI 3,with 400bhp and 360lbs/ft,with no problems at all.You wouldn't even know it was an uprated clutch as the feel is just like standard.I've also had 2 HELIX clutches which lasted around 6000 miles each.This one has done approx 8000 miles and still feels as good as the day i had it put in.....;)...Alan...

mark,

I notice in scoobyshop that your clutches are advertised with a clamping pressure of 1400kg. it also says that each cover is individually tested to a 1.5% tolerance.

can you post any certificates or other documents that can back your claims up?

the clutch covers are very similar(diaphragm , with as much as I can get to measure seem the same) and the only real difference I can find is the addition of a machined ring between the diaphragm and pressure plate. both clutches share 9 lugs on the pressure plate, these hold the diaphragm into the cover. the UK's lugs are longer and press equally around the diaphragm(spaces between the lugs), the lateral has shorter lugs , with this ring making the difference up and it's located between the lugs and the diaphragm(no spaces). this ring ***may*** increase the angle of the diaphragm . it is hard to explain but this ring is on the wrong side to "really" increase the clamp rate by much (IMO) , but could increase the angle the spring works at but I will need to try and work out a way to measure the working angle between the two covers.

I can't actually see how the clutch could offer 44% more over a UK99> 230mm clutch , let alone the further increase offered over a STI/AP version , if they come in clamping at 1050kg.



[Edited by T-uk - 12/29/2003 6:37:43 PM]

Just changed my Lateral perf 5 paddle clutch after 22000 miles - it was just into the rivets. No track days - but this clutch gives the impression it WONT slip when engaged. It was not good in prolonged stop start traffic queues (with 5.4kg f/wheel) -but I rarely suffer with those so I was happy with its "character" overall. :)
Stan