New RPS Twin Disk Clutch Review

We tested RPS' twin disk carbon/organic clutch late last night and the results were fantastic!!!

Rob from RPS designed a new clutch which incorporates a carbon and organic disk combination. The clutch is quiet, chatter free, and engages very smoothly. The pedal feel and engagement is nearly identical to the RPS Single Disk unit. Rob calculated that this clutch should be able to hold well over 700 ft/lbs of torque so we decided to put it to the test.

Our dyno appointment ran late so we had to stop at 24 psi which netted 771 hp and 548 ft/lbs of torque at the rear wheels on a Mustang Chassis dyno.

HUGE THANKS to Rob Smith from RPS for thinking up such a great product that performed exactly as designed right out of the box! Rob says this clutch will be available from RPS dealers very shortly.

Scheduling another dyno appointment to turn up the boost even more. I'll be posting clutch installation pics and details later today or tomorrow.

Is this Twin Disk Clutch for 5 speed only? what is the cost for this clutch system? How long is the break in?

can this be used on factory dual disc nsx's (ie 97+) ?

i don't know what the pedal pressure is on a rps single disc, so how does the pedal pressure compare to stock?

what is the weight of this clutch and pressure plate?

thanks

Tinker219 said:

We tested RPS' twin disk carbon/organic clutch late last night and the results were fantastic!!!

Click to expand...

Something in this combination I don't understand. You say this combination can hold more than 700 lbs of torque. The clutch uses two disks with different slip coefficient of friction. This means that one of the two disks can hold more than the other (the carbon disk I assume). It is like a chain that is as strong as its weakest link. Slip will occur first with the organic disk while the carbon disk will stay engaged. So the double clutch disk will behave like a one disk clutch. This is probably the reason why it is so smooth. It is like you have a one organic disk clutch.

nsxman2001 said:

Is this Twin Disk Clutch for 5 speed only? what is the cost for this clutch system? How long is the break in?

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The RPS Street Twin clutch fits both the 5 and 6 speed cars. The list price is $2,995.95 and the break in period is 500 miles of stop and go driving.

Rob Smith
President, RPS

socalx said:

can this be used on factory dual disc nsx's (ie 97+) ?

i don't know what the pedal pressure is on a rps single disc, so how does the pedal pressure compare to stock?

what is the weight of this clutch and pressure plate?

thanks

Click to expand...

Yes this new clutch will fit both the single and twin disc cars.

The Street Twin uses the same great pressure plate we have used for years on our single disc. As anyone who has one of our single disc clutches knows, the pedal is stiffer than stock. This stiffer pedal is exactly why our clutches hold so much power.

The entire twin disc clutch and flywheel assembly weighs approx 27 pounds.

Gerard van Santen said:

Something in this combination I don't understand. You say this combination can hold more than 700 lbs of torque. The clutch uses two disks with different slip coefficient of friction. This means that one of the two disks can hold more than the other (the carbon disk I assume). It is like a chain that is as strong as its weakest link. Slip will occur first with the organic disk while the carbon disk will stay engaged. So the double clutch disk will behave like a one disk clutch. This is probably the reason why it is so smooth. It is like you have a one organic disk clutch.

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Thank you for your post. This subject can get very confusing. The most important thing to remember about twin friction clutch discs is that the two different materials are attached to the same metal plate, so one side can not slip without the other slipping. So in a sense this is a chain that is as strong as the strongest link.

RPSTC said:

Thank you for your post. This subject can get very confusing. The most important thing to remember about twin friction clutch discs is that the two different materials are attached to the same metal plate, so one side can not slip without the other slipping. So in a sense this is a chain that is as strong as the strongest link.

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Thanks for the explanation.

Thanks for the information Rob smith..I'm still wondering since it's good for the 6 speed do u still need the Nsx-r input shaft to use this twin clutch for 97-05 trans? I know if u want to use a factory twin clutch from 91-96 you need it..hope this is not a dumb question.

thanks jermaine

What is the typical life of these clutches? and how much stiffer than stock?


OT:Gerard I love your avatar car looks mean!

nsxman2001 said:

Thanks for the information Rob smith..I'm still wondering since it's good for the 6 speed do u still need the Nsx-r input shaft to use this twin clutch for 97-05 trans? I know if u want to use a factory twin clutch from 91-96 you need it..hope this is not a dumb question.

thanks jermaine

Click to expand...

There are no dumb questions! Yes you need the longer input shaft.

ediddynsx said:

What is the typical life of these clutches? and how much stiffer than stock?


OT:Gerard I love your avatar car looks mean!

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As a rule of thumb, a twin disc clutch will last twice as long as a single disc clutch if the car is exactly the same and it is driven exactly the same. If you go to the Street Twin and also add a blower, NOS or a turbo than you may only get the same clutch life or even less depending on how big your up-grade is, but you will do it with a much bigger smile!

Just thought I would throw up another huge thanks to RPS for relieving me of the frustration of having the power with no way to put it to the ground!

This clutch is amazing on the street! While running more boost than my previous clutch, this thing is holding everything I've thrown at it so far without a hint of slippage.

Rob,
Where you at NOPI in ATL this year?

92NSX said:

Rob,
Where you at NOPI in ATL this year?

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No, I did not get to travel much this year. Maybe next year.

Below are some pictures of the clutch installation steps.

One of the most interesting steps that were relayed to me was the use of lapping compound on the disc and input shaft splines. Rob from RPS said that this is a step they perform at their facility before the clutches are shipped. The procedure requires a small amount of cylinder head valve lapping compound to be applied to the splines followed by sliding the disc back-and-forth on the input shaft, rotate the disc position a tooth, back-and-forth on the disc, rotate, and so on. After this was performed with both discs, the disc and shaft splines were carefully cleaned with brake cleaner in preparation for the next steps.

Rob also made sure we applied some synthetic bearing grease on the input shaft collar that rides inside of the throwout bearing and slid the pressure plate / throwout bearing assembly onto the shaft a couple of times prior to bolting the clutch together. Any excess grease was wiped off.

A very thin layer of anti-seize compound was applied to the clean input shaft splines using a brush and both discs were slid back-and-forth on the shaft similar to the lapping step above prior to the clutch being bolted together. Excess compound was removed so that there was no chance it might throw up onto the discs during operation.

Factory torque specs and sequence were used on the supplied flywheel to crank bolts with a drop of blue locktite. The 9 pressure plate to flywheel bolts were carefully snugged down in factory sequence 1/2 turn at a time until the pressure plate mated to the flywheel. A drop of blue loctite was also used and the bolts were torqued in factory sequence to RPS' specs.

If anyone has any questions about this, please let me know and I will try to help. I think the steps that were relayed to me above, especially the lapping, cleaning, and careful lubrication of the parts made a HUGE difference with how smooth this clutch performs.

Nice write up.

This clutch uses the stock slave cylinder/throwout bearing setup?

Any comments on the feel vs the single disc RPS? Is it same, similar, differet etc?

This clutch uses the stock slave, fork, and same pull-type throwout bearing as the single disc RPS.

The twin disc acts just like the single disc version - pedal pressure is identical. Engagement is just slightly different between the two.

when will this clutch be released? Can`t find it on RPS homapage

http://www.turboclutch.com/billet.html

Are you able to rebuild this clutch/flywheel? How much would it cost?

Sounds good. Is there a new throw out bearing provided with the kit?

thanks

http://www.vividracing.com/catalog/...id=8&my_value=26&class_8=26&products_id=30664

looks like a nice clutch

aside from the issues i had with my first RPS, the single disc setup is sweet. very solid engagement, and pedal pressure isn't bad once you get used to it.

would def go this route if i had high power.