What Gives?: Twin Disc Systems by the numbers
it's probably your throw out bearing rattling, not the clutch, they just have a problem with being pissy, unless it's REALLY bad, it should stop after a while when the throw out bearing settles a little bit better, mine did that and now it doesnt, most of the time
Originally Posted by MattGold
Disc chattering is in NO WAY due to incorrect installation, or in anyway a problem with your clutch. It is just an inherant problem of *any* twin disc.
-M
-M
you do not have to depress the clutch at a light in neutral, if you do your just wearing the bearing out...the bearing is a sealed lubricated bearing
Originally Posted by trinydex
uhm... i leave my car in neutral when i'm at a light... so i don't think my clutch is broken... btw... is it bad to leave a car in neutral without depressing the clutch... i heard something about the throw out bearing not being lubricated but i might have the context all wrong.
unless the bearing is wearing out it shouldnt be rattling.. its attached to the pressure plate. unless its not clipped in all the way... or for some odd reason the t.o.b. fork, the rod that holds it is worn out.. these bearings are attach. to the clutch, not like most other cars where the bearing just rides on the p.p.
ah ic that musta been it... riding it while at a stop is just wear...
my opinion is this... i regularly see gt40's car with his ACT leg press... and as long as mine doesn't sound like a buncha touchy feely artists making music on sewer pipes everytime i'm off my clutch (in his case on his clutch) i'm fine...
my opinion is this... i regularly see gt40's car with his ACT leg press... and as long as mine doesn't sound like a buncha touchy feely artists making music on sewer pipes everytime i'm off my clutch (in his case on his clutch) i'm fine...
As Far As Exedy Goes, I'm Not Trying To Deter Anyone From Buyin The Twin Disk But Personally That Is The Clutch I Wanted Until I Took Out My Friends When I Was Doing His Engine Rebuild And It Looked Like ****. Warped, Heat Spots On Every Surface Etc..... Had To Spend Almost 300 To Get Everything Resurfaced And $299 For Each Replacement Disk. Luckily For Him He Didnt Have The Carbon On Carbon One Because I Talked To Exedy And Those Are 600 A Piece To Replace Although That Set-up Should Last Longer. Clutch Wasn't Beat On All The Time Either. Just The Occasional Thing.so I'm Personally Looking Into Other Clutches. Not Sure What To Get Though. Where I Dyno My Car At They Also Religiously Sell The Rps Carbon On Carbon Clutches. Those Are Also 1000 More Than The Exedy Twin Also. But Rebuild On The Rps Is Half The Cost Of An Exedy Unit. Just My Thoughts.....
Originally Posted by quinnwhipple
Your triple makes less noise than your double because a pressure plate has a fixed amount of release, when you spread that across your 3 plates the total distance is less making the total assembly tighter
I believe that you can ask for a clutch to hold 600-700#'s of torque and still have it be stock clutch quiet. People that listen to my 2 plate RPS can't believe how quiet it is. It is as quiet as my stocker that we removed from the car.
As far as the current horse power level of our company car... It hasn't been dynoed in it's current configuration. This time of year the car is normally apart (winter time) for research. I put it back to gather to drive while my truck is getting fixed by the dealer. When the truck is done, the evo will get taken back apart to receive the remainder of it's winter updates. I don't know how some of these new internal parts will work. They are fresh designs that have to be tested. As you know with product development, some fresh parts are hits and some are duds. These new parts are founded on solid engineering, but what looks good on paper, and what works correct in a car are different things. I will say that the car makes good solid power but no paper dyno numbers to back it up. We scheduled our AWD dyno time during the month of May when we are on our next trip back east. As you know every dyno is a bit different. This is why we are traveling to a dyno that has other reference data that we wish to compare our data against.
I believe that you can ask for a clutch to hold 600-700#'s of torque and still have it be stock clutch quiet. People that listen to my 2 plate RPS can't believe how quiet it is. It is as quiet as my stocker that we removed from the car.
As far as the current horse power level of our company car... It hasn't been dynoed in it's current configuration. This time of year the car is normally apart (winter time) for research. I put it back to gather to drive while my truck is getting fixed by the dealer. When the truck is done, the evo will get taken back apart to receive the remainder of it's winter updates. I don't know how some of these new internal parts will work. They are fresh designs that have to be tested. As you know with product development, some fresh parts are hits and some are duds. These new parts are founded on solid engineering, but what looks good on paper, and what works correct in a car are different things. I will say that the car makes good solid power but no paper dyno numbers to back it up. We scheduled our AWD dyno time during the month of May when we are on our next trip back east. As you know every dyno is a bit different. This is why we are traveling to a dyno that has other reference data that we wish to compare our data against.
My Exedy Twin for the first 2500 miles or so (break in and drag time) didn't make a sound, but after tolarances loosened up a bit (as any clutch will) it started to make a sound. Not as loud and let's say, an exhaust or a BOV, but a sound none the less.
I think that after you put you car back together and get some miles on your setup it *might* be noiser then it was at day one.
Regardless, I don't see "noise" as being a deciding factor in clutch selection... Power level and streetability is.
As for your concerns about the Exedy being not streetable, or hard to slip... I think that *any* owner of the Exedy can attest that that is furthest from the truth. Exedy designes their clutches with a "cushion zone" for half engagement, which makes it very easy on the street.
Good luck with everything...
-M
Originally Posted by quinnwhipple
The Exedy twin carbon is Carbon/Steel. If you want personal testimony on the Exedy Carbon Twin give Tym Switzer a call at Switzer Performance Engeneering. He will tell you how much he hates it in his daily driver. Noise and doesn't fully hold stock horsepower levels when cold. The clean shifting is comming from most of the 2 disk units not having any marcel in the plates.
https://www.evolutionm.net/forums/sh...0&page=2&pp=15
To pull the details of this thread:
Originally Posted by evoviiiyou
Mike, Tim says to go with the Exedy trip. because he has good experience with it and he know it can handle my porer level with stock like drivability. I listed this thread in order to get some sort of education in order to talk to Tim on some what of an intelligent level. I was just curious as to the details and all of this info has helped a ton. In the end I told Tim this evening to go with the trip exedy. He told me that the trip exedy is not carbon on carbon so it will be quite quiet compared to the carbon carbon dual disk set up he runs on his wifes evo. Thanks again every one.
.
.
So which is it? Maybe Tym will chime in on this.
-M
Tym should have a triple disc in his EVO actually, that's what he had for it when he left our shop.
We have had better success with the Exedy twin disc clutch than we have out of any clutch we have ever run in all the years of building AWD cars. The engagement is the smoothest, the pedal pressure is the most liveable.
I don't personally like the rattling sound ANY of the multi disc clutches make.
We recommend the twin disc Exedy to all of our customers up to Stage 4 modifications. That will put up to 400 whp to the ground. I can't think of a failed twin disc unit yet that has had 400 whp or less come back.
Now, when we started making some big power numbers with our red EVO the twin disc did not hold up. At the end of last year, although we never posted or talked about this, we took the EVO to the track. The car was as sorted out as it was going to get and we attempted to run a good number. The car had the twin disc in it. My brother was driving and I was standing just before the 1/8th mile marker. I could hear him launch and the engine hit the rev limiter. I thought it was spinning the tires. As he switched gears I could hear it hit the rev limiter again. As he passed me in 3rd gear I could still here the RPM's not matching how the car was accelerating. When he came down the return road he told me the clutch was slipping. A few more attempts and he left the track pissed off. At this point I am going to say the car was making right around 575 whp, which the 11.1's at 127 did not reflect due to the clutch slipping.
We tried to order a triple disc, they were out of stock and we were in a hurry to get back to the track before it closed for the year. We ordered an ATS triple, this clutch converts the car from a pull type pressure plate to push. We were promised the clutch in 3 days. Almost 3 weeks later when it actually showed up the track was closed for the year. The pedal pressure is just not user friendly. Horrible is how I would rate it. Would not have it in my own EVO. VERY VERY aggressive, I highly doubt it will ever slip but I also think it will leave many driveline parts on the ground if the launches are done carefully.
RPS, had many many offers to sell their product. I was on the edge of trying them when I got numerous reports about problems with them. One of the guys that have had multiple problems it is on here commenting about liking certain aspects of it.
We have a customer car in here now that makes over 500 whp, he has went through 2 Exedy twins. With the HP level of the car it isn't something we recommend using anyway. We were going to put an Exedy triple in the car, they were on back order. Customer HAD to have the car so we put in the order for the RPS that the customer decided he wanted to use.
As with many of the RPS clutches we heard about the starter to flywheel engagement is NOT right. Well after installing this one that was gauranteed to not have any problems....it does. The starter when engaged drags so bad that the car sounds like some piece of **** you drug out of the junk yard. We called about it and were told after 20-30 starts it would "wear in". BS, BS, BS, BS!! This clutch sells for $2600, it shouldn't have to "wear in". The customer contacted them and has a verbal "lifetime warranty" on the flywheel and starter. Fine with us. I would not tolerate it in my personal car, customer wants it....fine with us.
I am hoping this RPS clutch is the world's greatest clutch and we don't have to pull it back out. When we do the customer will have to pay again as he was told this before we put it in.
As for Exedy clutch assembly weights, Logic you are just plain flat our wrong. Flat out.
The Exedy twin plate actually weighs in at a half pound LESS than the stock unit and the twin disc weighs under 35 pounds IN THE BOX THAT IT COMES IN!
David Buschur
www.buschurracing.com
We have had better success with the Exedy twin disc clutch than we have out of any clutch we have ever run in all the years of building AWD cars. The engagement is the smoothest, the pedal pressure is the most liveable.
I don't personally like the rattling sound ANY of the multi disc clutches make.
We recommend the twin disc Exedy to all of our customers up to Stage 4 modifications. That will put up to 400 whp to the ground. I can't think of a failed twin disc unit yet that has had 400 whp or less come back.
Now, when we started making some big power numbers with our red EVO the twin disc did not hold up. At the end of last year, although we never posted or talked about this, we took the EVO to the track. The car was as sorted out as it was going to get and we attempted to run a good number. The car had the twin disc in it. My brother was driving and I was standing just before the 1/8th mile marker. I could hear him launch and the engine hit the rev limiter. I thought it was spinning the tires. As he switched gears I could hear it hit the rev limiter again. As he passed me in 3rd gear I could still here the RPM's not matching how the car was accelerating. When he came down the return road he told me the clutch was slipping. A few more attempts and he left the track pissed off. At this point I am going to say the car was making right around 575 whp, which the 11.1's at 127 did not reflect due to the clutch slipping.
We tried to order a triple disc, they were out of stock and we were in a hurry to get back to the track before it closed for the year. We ordered an ATS triple, this clutch converts the car from a pull type pressure plate to push. We were promised the clutch in 3 days. Almost 3 weeks later when it actually showed up the track was closed for the year. The pedal pressure is just not user friendly. Horrible is how I would rate it. Would not have it in my own EVO. VERY VERY aggressive, I highly doubt it will ever slip but I also think it will leave many driveline parts on the ground if the launches are done carefully.
RPS, had many many offers to sell their product. I was on the edge of trying them when I got numerous reports about problems with them. One of the guys that have had multiple problems it is on here commenting about liking certain aspects of it.
We have a customer car in here now that makes over 500 whp, he has went through 2 Exedy twins. With the HP level of the car it isn't something we recommend using anyway. We were going to put an Exedy triple in the car, they were on back order. Customer HAD to have the car so we put in the order for the RPS that the customer decided he wanted to use.
As with many of the RPS clutches we heard about the starter to flywheel engagement is NOT right. Well after installing this one that was gauranteed to not have any problems....it does. The starter when engaged drags so bad that the car sounds like some piece of **** you drug out of the junk yard. We called about it and were told after 20-30 starts it would "wear in". BS, BS, BS, BS!! This clutch sells for $2600, it shouldn't have to "wear in". The customer contacted them and has a verbal "lifetime warranty" on the flywheel and starter. Fine with us. I would not tolerate it in my personal car, customer wants it....fine with us.
I am hoping this RPS clutch is the world's greatest clutch and we don't have to pull it back out. When we do the customer will have to pay again as he was told this before we put it in.
As for Exedy clutch assembly weights, Logic you are just plain flat our wrong. Flat out.
The Exedy twin plate actually weighs in at a half pound LESS than the stock unit and the twin disc weighs under 35 pounds IN THE BOX THAT IT COMES IN!
David Buschur
www.buschurracing.com
FWIW,
I had the HKS GDmax twin disc. It lasted about 35 1/4 miles passes and 5 1/8 miles passes. I had the TSB done on the transmission about a month ago. I found the disc closest to the flywheel was almost completely gone. The one disc sandwiched (the one furthest from the flywheel) was worn about half out. The flywheel and the secondary flywheel had alot of hot spots on it. Also, the disc that was virtually worn out was not worn evenly. It was worn more on the outer diameter of the disc than the inner diameter. It appears that my disc had some warpage as well. I am still running the stock turbo with larger housing. My clutch has a total of about 5500 miles on it.
There seems to be a fundamental design flaw in this clutch mechanism, I don't know if this clutch is made partially by Exedy, becuase HKS uses a different TOB attaching mechanism. I believe the friction materials are similiar though.
I agree that the twin discs will hold alot of torque, but hard drag race launches will cause high wear. I think the triple disc or high capacity pressure plate from Exedy would be a better solution for a drag racer, (no matter how low the torque). It is my opinion that it is the shock loading capacity that is the critical issue in these clutches wearing prematurely, not just torque holding capacity.
The static friction is much higher than the kinetic friction. The kinetic friction is what is involved during the launch. Once engaged fully the static friction creates more than enough holding to hold virtually all the power ANY Evo can make.
Brian
I had the HKS GDmax twin disc. It lasted about 35 1/4 miles passes and 5 1/8 miles passes. I had the TSB done on the transmission about a month ago. I found the disc closest to the flywheel was almost completely gone. The one disc sandwiched (the one furthest from the flywheel) was worn about half out. The flywheel and the secondary flywheel had alot of hot spots on it. Also, the disc that was virtually worn out was not worn evenly. It was worn more on the outer diameter of the disc than the inner diameter. It appears that my disc had some warpage as well. I am still running the stock turbo with larger housing. My clutch has a total of about 5500 miles on it.
There seems to be a fundamental design flaw in this clutch mechanism, I don't know if this clutch is made partially by Exedy, becuase HKS uses a different TOB attaching mechanism. I believe the friction materials are similiar though.
I agree that the twin discs will hold alot of torque, but hard drag race launches will cause high wear. I think the triple disc or high capacity pressure plate from Exedy would be a better solution for a drag racer, (no matter how low the torque). It is my opinion that it is the shock loading capacity that is the critical issue in these clutches wearing prematurely, not just torque holding capacity.
The static friction is much higher than the kinetic friction. The kinetic friction is what is involved during the launch. Once engaged fully the static friction creates more than enough holding to hold virtually all the power ANY Evo can make.
Brian
at the rate were going here, everyone who drags the car should convert to a powerglide trans. ford 9 inch rear, probs solved.. it seems no matter how much we beat this topic, there is still no good answer.. or is there, uk, japan, europe, these countries have had every version of the evo.. but nobody in all these years has come up with a strudy clutch? tested and proven... after all exedy did design the horrible clutch that came factory on our cars. or we could blame mitsu. for being cheap. both are prob. true....its not like the evo hasnt been around long enough for r-d.. oh well one day we'll have a clutch that can handle the beating, and trans gears made out of rubber.. no more grinding..
Originally Posted by davidbuschur
As for Exedy clutch assembly weights, Logic you are just plain flat our wrong. Flat out.
The Exedy twin plate actually weighs in at a half pound LESS than the stock unit and the twin disc weighs under 35 pounds IN THE BOX THAT IT COMES IN!
here are the Exedy Twin and RPS Twin on the scale
dru
Originally Posted by TURBODAWG
FWIW,
I had the HKS GDmax twin disc. It appears that my disc had some warpage as well. I am still running the stock turbo with larger housing. My clutch has a total of about 5500 miles on it.
There seems to be a fundamental design flaw in this clutch mechanism, I don't know if this clutch is made partially by Exedy, becuase HKS uses a different TOB attaching mechanism. I believe the friction materials are similiar though.
I agree that the twin discs will hold alot of torque, but hard drag race launches will cause high wear. I think the triple disc or high capacity pressure plate from Exedy would be a better solution for a drag racer, (no matter how low the torque). It is my opinion that it is the shock loading capacity that is the critical issue in these clutches wearing prematurely, not just torque holding capacity.
The static friction is much higher than the kinetic friction. The kinetic friction is what is involved during the launch. Once engaged fully the static friction creates more than enough holding to hold virtually all the power ANY Evo can make.
Brian
I had the HKS GDmax twin disc. It appears that my disc had some warpage as well. I am still running the stock turbo with larger housing. My clutch has a total of about 5500 miles on it.
There seems to be a fundamental design flaw in this clutch mechanism, I don't know if this clutch is made partially by Exedy, becuase HKS uses a different TOB attaching mechanism. I believe the friction materials are similiar though.
I agree that the twin discs will hold alot of torque, but hard drag race launches will cause high wear. I think the triple disc or high capacity pressure plate from Exedy would be a better solution for a drag racer, (no matter how low the torque). It is my opinion that it is the shock loading capacity that is the critical issue in these clutches wearing prematurely, not just torque holding capacity.
The static friction is much higher than the kinetic friction. The kinetic friction is what is involved during the launch. Once engaged fully the static friction creates more than enough holding to hold virtually all the power ANY Evo can make.
Brian
dru
now what is this that the flywheel is not lining up.. why hasnt anyone ever said anything before.. or is this just a fluke.. that is a big prob in my books. and a purchasing factor..