Jump to content
  • Welcome to 205GTIDrivers.com!

    Hello dear visitor! Feel free to browse but we invite you to register completely free of charge in order to enjoy the full functionality of the website.

SweetBadger

Reliable Race Clutch Pressure Plate Required - Any Ideas?

Recommended Posts

SweetBadger

Hey all, back from yet another disappointing race at Silverstone - all was going well, up to 3rd in class but 14 laps in the clutch let go again :-( . Pressure plate springs went making it difficult to change gear and then took out the crank sensor.

 

This is the second time this has happened - both genuine Valeo pressure plates; the springs are just breaking up.

 

 

Last season we ran a standard Valeo clutch all season with no problems (mildly tuned 1.9 mi on bodies - red line @ 7800 rpm but usually didn't see that).

 

This season with the new car we have a Gti6 race engine 194 bhp @ the wheels - sees 8000rpm regularly. I think the standard pressure plate can't handle the combination of higher rpm & added torque from the new engine.

 

We had a solid centre helix paddle clutch in for the first two races of the season, so assumed the very snatchy nature of the clutch plate caused the pressure plate to fail. Decided to run a totally standard clutch and the same thing happened, so it wasn't down to the paddle clutch.

 

 

Any recommendations for a reliable 215mm race pressure plate?

 

Note it doesn't have to have a higher than standard torque capacity; the standard clutch never slipped and we don't want to unnecessarily increase the pedal force required to operate the clutch.

Share this post


Link to post
Share on other sites
Liam

​following this

​

Share this post


Link to post
Share on other sites
parry

Did you try the helix pressure plate that is suited to the helix clutch?

Share this post


Link to post
Share on other sites
Biggles

I had a problem on my 1600 with the (smaller dia) clutch breaking up. The conversation I had with a chap at Helix pretty much pointed the finger at the rpm it was seeing (limiter is at 8500rpm). The only solution was to go to a 7.25" race clutch - which has been in 2 years now. It could be you're seeing something similar. Might be worth a similar conversation - I can probably dig out the chap's details if you're interested.

Share this post


Link to post
Share on other sites
welshpug

yep, its the revs that do it, have seen a few of the castle combe racers with TU and a few others have issues with pressed steel clutch plates, though not seen what they have used instead.

 

I know the Saxo I service for uses a C2 R2 clutch.

 

http://boutique.citroenracing.com/product.php?id_product=2664

Share this post


Link to post
Share on other sites
Rippthrough

Pressure plate is only ever from RPM's or overstroking them. I'm running a 200SX push plate on the buggy which is about 225mm, and the OE s2000 pull-type one is only a little smaller diameter at about 215mm - both the OE pressure plates are balanced to G6.3 @ 10krpm

Edited by Rippthrough

Share this post


Link to post
Share on other sites
welshpug

so the trick is to use a Honda clutch?

 

will they cope with the torque? :P

Share this post


Link to post
Share on other sites
Rippthrough

I think they might just :D

Share this post


Link to post
Share on other sites
Tom Fenton

Well if they can cope with VTEC YO!.....

Share this post


Link to post
Share on other sites
SweetBadger

Heheh! :lol:

 

 

@Parry, Never tried the helix pressure plate - car came with a standard pressure plate and the helix paddle clutch - changed it out for a standard item the first time it went.

 

 

Think I got my clutch terminology mixed up in the first post - It's the drive straps that are breaking, the sprung bit of the pressure plate has stayed intact but when you remove the clutch the three drive straps are MIA (or embedded in the crank sensor!) and the clamping plate falls out.

 

Pics of the 1st one that failed:

 

3A9F251A-50EC-4443-A663-CDE0589CBDDB.jpg

 

FC13305A-F16B-4989-97DA-65E2DB73CFD2.jpg

 

 

Is this still an rpm related failure?

 

If so, guess it's time to look for a balanced pressure plate, want to stick with a 215mm unit if possible as we have a TTV 215mm steel flywheel already fitted.

Share this post


Link to post
Share on other sites
petert

Big downshifts?

Edited by petert

Share this post


Link to post
Share on other sites
SweetBadger

Try not to - with the pedal box in the new car heel toe is easier to do (although still not happy with where the standard pedals sit), and I'm a lot easier on the drive-train than I was when we first started racing last season. Could be that the new engine being higher compression is harder to accelerate so when a big downshift does happen it puts too much stress on the clutch?

 

I've dropped an email to Spec to see what they recommend as I read a few people of here have used them.

 

@biggles, would be good to get the contact details for the guy at Helix if you could dig them out.

Share this post


Link to post
Share on other sites
Biggles

 

 

Is this still an rpm related failure?

 

If so, guess it's time to look for a balanced pressure plate, want to stick with a 215mm unit if possible as we have a TTV 215mm steel flywheel already fitted.

 

Exactly the same failure mode as mine. Rpm induced, pure & simple from what the chap told me. Nothing you can do about it either hence me going to a 7.25" race clutch - along with the flywheel to match :-( .

 

Will dig out contact details for you.

Share this post


Link to post
Share on other sites
petert

Call it RPM or whatever, a std. pressure plate is never going to work. I "think" this what is happens. The straps are normally in tension, a situation in which they'll outlast the clutch plate. When you down change at high RPM however, the load is momentarily reversed on the straps, putting them into compression/buckling. A situation aggravated with sticky tyres. At this point they fail and take out whatever is near them.

  • Like 1

Share this post


Link to post
Share on other sites
petert

And as Adrian Wuillemin rightly pointed out, each time you do a down change, you're work hardening the straps. Sell your flywheel etc. and buy 7.25".

Share this post


Link to post
Share on other sites
welshpug

youll have plenty of buyers for the 215mm flywheel :)

Share this post


Link to post
Share on other sites
SweetBadger

Yup, looks like we're going to have to bite the bullet and swap the flywheel then get a lug clutch.

 

Thinking the 184mm 220nm single plate helix Cerametallic clutch cover and 6 paddle Cerametallic plate should do the trick (the car still gets used on the road sometimes to get to and from tracks so this should be better suited to that).

 

Spec responded with similar comments - their strapped clutches are much stronger than standard but they couldn't guarantee that they wouldn't fail under race conditions, the one they recommended was their strapless unit which is pricey (also requiring our flywheel to be re-drilled). The contact that Biggles provided said the same thing about the up-rated Helix strapped clutches.

 

Considering the cost of a race entry is close to the cost of a race clutch setup, it doesn't make sense to try an up-rated strapped clutch.

Edited by SweetBadger

Share this post


Link to post
Share on other sites
Biggles

One thing to be aware of is the release force on a race clutch is higher than a road clutch. Is the car hydraulic or cable ? If it's cable, you may well see a significant increase in the pedal effort required. I've got a similar spec clutch to the one you're looking at - cable operated - and needed to modify both pedal and release arm in order to get an acceptable pedal effort. It's still heavier than I'd like so when I've worn it out I'll be replacing it with a twin plate one.

Share this post


Link to post
Share on other sites
Miles

As above I have seen the case crack due to the 7 1/4" clutch used and they are heavy, If a BE3 cable you will need to mod the end from plastic to metal without a doubt along with a adaptor for the release bearing

Share this post


Link to post
Share on other sites
petert

AP offer three different clamp pressures/release pressures in their single plate 7.25". And that's the problem with a 7.25" single plate, you need a lot of clamping pressure to make up for the reduction in diameter. A twin plate requires less clamping pressure.

Share this post


Link to post
Share on other sites
petert

eg. with a twin plate you can have 263Nm torque capacity with 160daN release load, compared to only 160Nm an 160daN release load on a single plate.

post-2864-0-77166000-1471996973_thumb.png

post-2864-0-52805000-1471996984_thumb.png

Share this post


Link to post
Share on other sites
SweetBadger

Ok that makes sense. Looking at the available options the 215mm single plate racing clutches all have a very high torque capacity so will still have a high release load.

 

I don't want to unnecessarily increase the pedal force required and we're running the standard clutch cable and arm, so it looks like a 184mm twin plate clutch is going to be the best option (guessing that's going to be even more £ ...!).

 

What a pita!

 

I'm surprised no one has ever made a strapped clutch cover with 6 straps, 3 in one direction, 3 in the other - it they're strong in tension you'd have 3 taking the acceleration forces and 3 taking the forces from a downshift.

Share this post


Link to post
Share on other sites
Rippthrough

The pressure plate moves around slightly as the straps flatten out so doing that would just put them all in compression and they'd fail anyway.

Share this post


Link to post
Share on other sites
Biggles

Ok that makes sense. Looking at the available options the 215mm single plate racing clutches all have a very high torque capacity so will still have a high release load.

 

I don't want to unnecessarily increase the pedal force required and we're running the standard clutch cable and arm, so it looks like a 184mm twin plate clutch is going to be the best option (guessing that's going to be even more £ ...!).

 

What a pita!.

 

More money but less of a pita of getting a single plate to be acceptable. My single plate was such a right royal pita that, with hindsight, I should have binned it, chalked it up to experience and bought a twin plate rather than tried to make it work.

 

Look on the bright side though - race clutch & flywheel to suit will be a lot lighter than what you've got now so the engine will spin up a lot faster :-)

Edited by Biggles

Share this post


Link to post
Share on other sites
SweetBadger

True, that will be an added bonus!

Right I think I have my shopping list sorted - going for the 184mm twin plate cerametallic AP racing clutch. Green diaphragm spring load rating, should be good for 267 NM which is more than enough for our engine.

So:

1 x AP Racing 184mm paddle clutch assy: twin plate lug drive (green) (part no CP7382-NH80-SF): http://www.burtonpower.com/clutch-assy-2xpaddle-lug-drive-green-cp7382-nh80-sf.html
2 x AP Racing 184mm 6 paddle clutch plate: 21.1x18 (part no CP4946-2)
1 x Racing flywheel (will get in touch with Rich W for a TTV one)
1 x Helix 55mm BE release bearing: http://www.spoox.co.uk/en/race-clutches/4731-peugeot-205-309-gti-be3-clutch-release-bearing.html

AP do release bearings but you have to get an adaptor made up to suit the BE clutch fork; the Helix one is specifically for a BE box. The AP clutches require a 54mm bearing and the Helix one is 55mm, but I don't think that'll be an issue.

This lot will set us back about £900 :o

Any comments, suggestions on the above?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×