What Clutch Do I Need?

[jckrieger]

I currently have a 6 puck ceramic clutch from Relentless Performance that was supposed to handle 350whp or some number along those lines. Well, I need something that handles more torque... and a lot more at that.

I'd like to have a heavy duty organic disc and a pressure plate that has some serious clamping force. Pedal feel isn't a huge issue, but the clutch MUST be daily driveable. Also, I'd like to know if I'll need to keep spare clutch cables in the trunk, and if a custom clutch adjuster should be required.

I noticed none of the vendors advertise an organic disc as being torque-capable. They also don't sell organic discs with decent pressure plates. Is this because they don't have good quality organic discs, or is this due to some other reason?

I'm currently looking at a Spec pressure plate and a custom Clutchnet organic disc. I'm also interested in a dual diaphragm pressure plate, but I'd like to know which one is going to work the best. Let me know what you guys think will work best... this clutch is going in my 87 CSX that ran 105.68mph at 21psi with a 10:1 A/F ratio... and will make another 100+hp with the boost turned up and the alcohol leaned out.

-Clark

[shelbyplaya]

what are your ET's?

I'm running a TU 6 puck with the yellow PP in my full street trim 87 Daytona Shelby Z with slicks.
No clutch issues whats so ever. the pedel feel was a bigh on the tight side but it was still drivreable on the street. NOT a good clutch for stop and go traffic!!!!

maybe you should look into getting the kevlar street/strip clutch with the up-graded PP or even the 6 puck from TU.

[jl93sundance]

what are your ET's?

I'm running a TU 6 puck with the yellow PP in my full street trim 87 Daytona Shelby Z with slicks.
No clutch issues whats so ever. the pedel feel was a bigh on the tight side but it was still drivreable on the street. NOT a good clutch for stop and go traffic!!!!

maybe you should look into getting the kevlar street/strip clutch with the up-graded PP or even the 6 puck from TU.

So would you recommend the 6 puck For a daily driven car?

[shelbyplaya]

So would you recommend the 6 puck For a daily driven car?

I would not. But It's a good option for a high torque car.


the kevlar street/strip clutch might be a good choise with the yellow PP.

[jckrieger]

I made 2 runs at the track at "low boost", first run was a 14.7@104.5 with a 2.7 60' and the second run was a 13.6@105.6ish with a 2.4 60'. I had a passenger both runs, and couldn't tell if the clutch was slipping or the tires in 1st or 2nd gear. In 3rd gear it was apparent that the clutch was gone. My fourth run was a 14.0@100mph because the clutch wouldn't hold in any gear.

[MiniMopar]

It was probably a stock T3 PP....

[moparzrule]

^Beat me too it Russ. Yes the relentless 6 puck clutch used a stock T3 PP. It was rated for 350 CRANK hp, but looks like it fell short. From the trap speed of 105 MPH in a CSX, you are slightly under 300 WHP.
Even a 6 puck with the yellow PP from TU would hold a lot more.
I dunno but people talk bad about the 4 puck and say it breaks, only because 2 people had issues with them. I have a 4 puck with the blue plate in my shadow, had ~300-325 WHP with a 2.5L with no issues. Now I'm going for 400 WHP with a 2.2, I'm not changing the clutch. I thought about upgrading to the yellow PP but Chris told me it should still hold because my shadow will be lightened some.
I find I have NO issues slipping the 4 puck on startoff, it takes a few hundred miles but you get used to it pretty quick. I would NOT want to get stuck in heavy stop and go traffic with any clutch that can handle 400 WHP. But the 4 puck is not near the on/off clutch I thought it was going to be, very manageable on the street.
And I have the 6 puck with blue plate in my daily driver. Honestly it's hard to tell thats it's not a stock clutch. But maybe thats because I'm used to the 4 puck LOL.
I also have used the ceramic/organic, but I used it with a dual diaphram PP in a daily driver(my old daytona). Although I don't recommend the dual diaphram plate(I happen to love extreme clutches), this disc may be a good option for you with a lesser plate. Perhaps the blue or yellow plate with the ceramic/organic may be a great combo for a daily driver with relatively high HP.

[jckrieger]

Just under 300whp at 21psi is doing pretty good, heh. If the disc is in good shape, I'll be trying the dual diaphragm pressure plate, the yellow plate, or the Spec Clutch 2300lb plate. I'm waiting for Chris to get back to me with a price on a new yellow plate.

[moparzrule]

Well looking at some HP calculators is about 275 WHP assuming about a 2900 pound race weight. But with 10:1 A/F you were really flogging it. With 11.5:1 A/F I bet you'd be trapping 110+.
I trapped 111 in my daytona, running 25 PSI. I dyno'd 290 WHP at 22 PSI on a hot humid day after the IC had already been heat soaked after 5 pulls working on tuning A/F starting out at 14 PSI. I don't know what my daytona weighed, maybe 3000. Not sure. It was only like 60 degrees out at the track that day, so that helped me too I suppose.

I highly recommend the yellow plate from TU. Although I never had any cable snapping issues with my dual diaphram, I don't really recommend it for something being driven on the street much because the pedal effort was pretty extreme.

[MiniMopar]

Yeah JT went through a few clutch cables on a dual diaphragm. I think he swapped it out in the end.

I just found my rusty old 6-puck in my scrap pile. It too is an RP and it has a Sachs PP. This was back in the day, so no modded PPs like now. Thus I'm sure it was a stock T3. Held OK for me, but I was probably somewhere in the 250HP neighborhood at best. It was replaced because it was just worn out.

I personally intend to avoid the 4-pucks until they change the design, but YMMV. It's just silly the way it is now. The 3-puck clutches at clutchnet don't seem to have the same issue. If I fry the Kevlar clutch in the Daytona, I'll probably go back to a 6-puck.

[shelbyplaya]

are the clutchnet clutchs any good? i was thinking of getting one but they look kinda sketchey

[jckrieger]

are the clutchnet clutchs any good? i was thinking of getting one but they look kinda sketchey

Last I heard Clutchnet pressure plates are a no-no. I'm thinking a kick---- combo would be a custom Clutchnet disc and the Spec 2300lb pressure plate from Cindy.

[moparzrule]

Wow $330 just for a pressure plate. I think the TU yellow plate is just as good as that one, for a lot less.

[shelbyplaya]

thats what i would do. But all in all. I would rather go with a PP and clutch from the same place. My personal prefernce is TU.

[jckrieger]

Wow $330 just for a pressure plate. I think the TU yellow plate is just as good as that one, for a lot less.

$330 is a lot for just a plate, but that plate can be used with any disc. I spoke with Chris W over the phone and he said I should use the yellow disc with a 4 puck ceramic disc. I've used organic and ceramic discs back to back, and I'm not sure there is much advantage to a ceramic over an organic disc. I think Chris quoted around $375ish for the yellow plate and a disc. Not bad at all, but I'd really like to get a kick arse organic clutch with a heavy plate. Oh well, we'll see what my 6 puck looks like and I'll go from there. I do think under $400 for a custom plate and disc is a good price, but it'd almost be worth trying a dual diaphragm plate with my 6 puck disc if I'm going to be sticking with a grabby ceramic clutch.

[MiniMopar]

I think the problem with organic lining is they tend to glaze due to heat more than other materials. A ceramic disc should be more resistant. A stronger PP will slip less but the increased pressure is still going to result in a lot of heat build up in the lining. But if you are willing to experiment I am interested to see what happens when you put a stock disc under a yellow PP. My gut feeling is that you won't like the results. :)

I think you had the right disc with the wrong PP.

[jckrieger]

I think the problem with organic lining is they tend to glaze due to heat more than other materials. A ceramic disc should be more resistant. A stronger PP will slip less but the increased pressure is still going to result in a lot of heat build up in the lining. But if you are willing to experiment I am interested to see what happens when you put a stock disc under a yellow PP. My gut feeling is that you won't like the results. :)

I think you had the right disc with the wrong PP.


Well, I won't use a stock disc because I'll blow it to pieces... but I might use a custom Clutchnet disc if a certain somebody gets me a quote...

As far as glazing goes, Chris told me I can't use my current ceramic 6 puck because it's probably glazed. Well, if my ceramic disc glazed like an organic, I might as well get an organic because I know it has the possibility of lasting 100K miles unlike a ceramic disc.

As far as heat goes, I actually feel that I had better luck in my old daytona with the T2/T3 organic clutch than I did with my 6 puck ceramic in my CSX. I've never had such terrible launches and bad slippage before, and this is the lowest mileage clutch I've ever had at the track.

[moparzrule]

Your ceramic disc got glazed because it didn't have enough plate pressure. Ceramic discs like more pressure. This is all cured with TU's blue or yellow plate.
An organic disc with a strong PP would be fine up to 300 WHP, but there's not way an organic will hold 400.

[shelbyplaya]

get the TU 6 puck. it's gonna be the best set up you can get. I was cracking 1.9 60's in a fulley loaded 87 daytona shelby z with 22 x 8 x 15" slicks with it. The motor was an 89 2.5l with a ported g-head, 15psi right off the line and a 4000 rpm launches. when i removed the PP/disk to install it in the 16v everything looked nice and clean still.

[jckrieger]

It looks like I got my stimulation from the government, so I might be ordering this clutch a little sooner than later. Maybe I'll save the 6 puck for the R/T when it needs a clutch in another 70K miles.

[moparzrule]

Darn you guys with direct deposit!