Clutch disc problem...

[brisvr4]

I purchased a Clutchnet clutch about 12 months ago and it has recently started to slip.
It is a sprung 6 puck with a 2x PP.
The car has only done approx 2100 miles since it was installed and I did break it in for approx 500 miles.
The friction pads actually seem to be disintegrating? I do run a Fidanza flywheel as well. I wonder if the screw holes in the friction surface on the flywheel have anything to do with it?
I do drag race the car but I would have though that a clutch would last longer than a oil change? /ubbthreads/images/graemlins/banghead.gif
It has probably been down the 1/4 maybe 20 times in the last year.

I have another clutchnet disc here but if it is going to die just as fast I won't bother installing it. I did notice that neither disc actually has the laser type etching that they show on their website?

 

[dmj]

Time to get the ACT 2600 with the street disc. this is a proven setup that can withstand a lot of heat unlike the clutchnet which you have to let cool down between runs . My other clutch lasted only about 2800 miles before slipping under full boost.right now I am driving with boost set a 10 psi so the clutch won't slip until I find the time to install the ACT.

 

[atc250r]

That sucks. I'm no clutch expert but I never understood why a clutch with 6 small pieces of friction material would be better than one with a continuous piece all the way around (like a street disc would be).

John

 

[fivestardsm]

Maybe Dialcaliper will chime in on that one. I don't think I would be able to explain it correctly. /ubbthreads/images/graemlins/idea.gif

 

[rgeier11]

It may be a repackaged POS. Where did you buy this from?

 

Quoting atc250r:
That sucks. I'm no clutch expert but I never understood why a clutch with 6 small pieces of friction material would be better than one with a continuous piece all the way around (like a street disc would be).

John



John the reason that is the case is the friction material on the pucks have a higher coeffiecent of friction than the organic material used in a full face disc. As a result, even though they have less surface area they can hold more torque than a full face organic disc.

If you were to have a puck disc made of organic friction material and compared it to a full face disc of the same organic friction material the puck disc would hold less torque because they both have the same coefficient of friction and the puck disc had less surface area.

Daryl

 

Quoting brisvr4:
I purchased a Clutchnet clutch about 12 months ago and it has recently started to slip.
It is a sprung 6 puck with a 2x PP.
The car has only done approx 2100 miles since it was installed and I did break it in for approx 500 miles.
The friction pads actually seem to be disintegrating? I do run a Fidanza flywheel as well. I wonder if the screw holes in the friction surface on the flywheel have anything to do with it?
I do drag race the car but I would have though that a clutch would last longer than a oil change? /ubbthreads/images/graemlins/banghead.gif
It has probably been down the 1/4 maybe 20 times in the last year.

I have another clutchnet disc here but if it is going to die just as fast I won't bother installing it. I did notice that neither disc actually has the laser type etching that they show on their website?




In the 4 years I worked for ACT that type of chipping of the friction material happened quite often. In most cases the clutch still functioned properly but if a customer sent one in it was most often repucked at no charge. Contact Jesse at Revolution and he can probably help you with that. You may also want to check the thickness of the pad to see if it was worn down past the minimum limit and caused the slippage you described instead of the chipped pucks.

It's not likely that the disintegration of the pucks was caused by the flywheel bolts.

Daryl

 

[turbowop]

Quoting vr4underboost:


If you were to have a puck disc made of organic friction material and compared it to a full face disc of the same organic friction material the puck disc would hold less torque because they both have the same coefficient of friction and the puck disc had less surface area.

Daryl



But since there is effectively more pressure on those smaller pucks compared to the pressure being spread out over a full face disk, isn't the pressure basically equalized as a whole? I always though the puck type unsprung hubs were just better for shifting since they were lighter?

 

[atc250r]

Then wouldn't it be better to make a disc that has the friction material of a puck type but all the way around like a street disc? Would it be too "grabby" at that point?

John

 

[brisvr4]

Quoting vr4underboost:



In the 4 years I worked for ACT that type of chipping of the friction material happened quite often. In most cases the clutch still functioned properly but if a customer sent one in it was most often repucked at no charge. Contact Jesse at Revolution and he can probably help you with that. You may also want to check the thickness of the pad to see if it was worn down past the minimum limit and caused the slippage you described instead of the chipped pucks.

It's not likely that the disintegration of the pucks was caused by the flywheel bolts.

Daryl



Thanks Daryl, I've just checked the friction surface wear and it isn't worn down as far as the rivets on any pad.
I've sent Clutchnet an email about it but from what I hear i'm not too hopeful about getting a fast reply!
I don't really want to hassle Jesse with this as he was fantastic when the original disc arrived damaged by USPS or Austpost ( not sure which ).
I just want a clutch that works for longer than an oil change that I can play with on the track!

Which ACT setup would you advise I get Daryl?
Presently I'm pushing 11's @ 120. No idea on HP but it can only go up /ubbthreads/images/graemlins/grin.gif

 

[Brianawd]

If you are going to be racing the car more looking into a twin. I know they are a lot of $ but well worth it.

As for ACT clutch's /ubbthreads/images/graemlins/uhh.gif I my self am not a fan. Other people my like than and they my work for them, but I always had problems with them dragging in the upper rpm's making shifting above 7k a real bitch. Spencer(4thstoke) has been having the same problem with his 2600 with a 6puck dragging at any thing above 7k. I don't know about u but I don't like getting locked out of the next gear. It not so good on the shift forks. Then tend to brake when that happens.

 

[iLLeffeKt vr-4]

Quoting dmj:
Time to get the ACT 2600 with the street disc. this is a proven setup that can withstand a lot of heat unlike the clutchnet which you have to let cool down between runs .



Act disks have the problem as the clutchnet disk posted above.
Click here to see the post I made about my friends act disk a while ago.

 

Quoting atc250r:
Then wouldn't it be better to make a disc that has the friction material of a puck type but all the way around like a street disc? Would it be too "grabby" at that point?

John



Yes John if you did a full face disc made of the same material as the puck disc it would be very grabby, and abrasive on the pressure plate and flywheel surface.

Daryl

 

Quoting turbowop:
Quoting vr4underboost:


If you were to have a puck disc made of organic friction material and compared it to a full face disc of the same organic friction material the puck disc would hold less torque because they both have the same coefficient of friction and the puck disc had less surface area.

Daryl



But since there is effectively more pressure on those smaller pucks compared to the pressure being spread out over a full face disk, isn't the pressure basically equalized as a whole? I always though the puck type unsprung hubs were just better for shifting since they were lighter?



Assuming that the clamp load on the pressure plate is equal, the only difference is the coefficient of friction of the material used on the disc. The higher that coeffiecent is the greater the torque capacity. In the case of a Quarter Master and PTT twin they are using a combination of surface area (via the 2 discs) and a higher coefficient of friction to allow a 7.25" diameter clutch to hold a great deal of torque with signnificantly less clamp load than a comparable single disc unit of the same size.

You are correct that the unsprung disc allows for faster shifting because they are lighter than a sprung hub of the same size. This works in much the same manner as the smaller diameter of the twin discs I mentioned above.

FWIW ACT is working on a 7.25 twin disc that should be released soon for the SRT4 and then for the DSM. I drove the SRT4 test car last week and I must say that I was impressed with the drivability and quick shifting. My Galant will most likely be the test car for the DSM clutches, even though I resigned from my job there last month.

Daryl

 

Quoting brisvr4:
Quoting vr4underboost:



In the 4 years I worked for ACT that type of chipping of the friction material happened quite often. In most cases the clutch still functioned properly but if a customer sent one in it was most often repucked at no charge. Contact Jesse at Revolution and he can probably help you with that. You may also want to check the thickness of the pad to see if it was worn down past the minimum limit and caused the slippage you described instead of the chipped pucks.

It's not likely that the disintegration of the pucks was caused by the flywheel bolts.

Daryl



Thanks Daryl, I've just checked the friction surface wear and it isn't worn down as far as the rivets on any pad.
I've sent Clutchnet an email about it but from what I hear i'm not too hopeful about getting a fast reply!
I don't really want to hassle Jesse with this as he was fantastic when the original disc arrived damaged by USPS or Austpost ( not sure which ).
I just want a clutch that works for longer than an oil change that I can play with on the track!

Which ACT setup would you advise I get Daryl?
Presently I'm pushing 11's @ 120. No idea on HP but it can only go up /ubbthreads/images/graemlins/grin.gif



You could use a 2600 with a 6 puck disc (MB1-XTR6), but like I said the chipping can occur on the puck material that ACT uses as well ( they might be from the same supplier) but the chipping exhibited typically does not cause the clutch to slip. If at all possible it would be a good idea to test the clamp load of the pressure plate. Because of your location that may not be feasible.

The other option is get a twin as mentioned by Brian or the ACT when it becomes available. The drawbacks are going to be initial cost along with a great deal of floater noise at idle (more of an issue when standing next to the car than when you're driving the car). Apart from that the twin is a good option for a car that visits the drag strip pretty often. Although I no longer work for ACT if you're interested in the ACT single disc set up PM me.

Daryl

 

[brisvr4]

Thanks Daryl, I can get the PP clamp pressure tested local to me so I think I will do that.
A little bit of rattling noise at idle won't worry me, you should hear the god awful sounds it makes now on decel /ubbthreads/images/graemlins/rofl.gif
If the present PP checks out I think I'll throw the spare clutch disc in it for now and save for a Twin plate.

 

[656of1000]

This was my ACT 2600 pressure plate after a year and a half in the car.

I vote for the twin.