Quarter Master Clutch - Sneek Peek Prototype design twin-disk!

[twicks69]

Fellow DSM'ers, I have some extremely cool pics to show all who are looking for a twin disk that can handle 1000+ torque without shearing the splines off the clutch disks!

Some of you on here know that my off-the-shelf Quarter Master 7.25" V-Drive Rally Twin Disk Clutch had sheared off all the splines on the clutch disks while I was on the Dyno back in July 2008. We were putting down 766AWHP and 713 Torque at all 4 wheels when this happened. These were the stock off-the-shelf disks from 2005.

Since then, Quarter Master has released an upgraded clutch disk with heat-treated hubs for the clutch disks. While this may be a good enough fix for most people, it wasn't for me. They worked great, but I still wanted to have a clutch that I could be assured would take all the abuse I put at it and not fail.

So.....

I spoke with Jeff Neal, President of Quarter Master Clutch when I was at the PRI Show (Performance Racing Industry) in Orlando, FL in December, and we talked about a new hub design that would reduce chatter issues along with strenghening the hub design by increasing its engagement surface area on the input shaft, and on the clutch disk so it would not fail. Jeff showed me a design they were working on, and I was very interested to see if it could handle the power I was putting down, so Jeff decided to let me be the test-bed for a complete prototype version of the clutch on my Eclipse!

I wouldn't say that the design is revolutionary, because the technology initially was used in a similar design for the carbon/carbon clutch hubs, but I believe it is the first of its kind for our application using a metal disk setup. Essentially, clutch disk splines now engage the entire length of the input shaft using one piece, whereas the original design, and every other design out there currently being used engages it using two separate pieces. The old clutch disks (current production pieces) engage at the most of 0.85" on the input shaft splines. The new hub design engages 1.55" of the input shaft splines with a single piece!!! The single solid piece design will definitely require you to have a good input shaft in the transmission, but will eliminate the issue of twisting off input shaft splines on high HP cars. The only way it would fail now, would be for the input shaft to snap in half! These separate pieces still engage most of the input shaft splines, but still chatter and cause harmonic issues.

This new design takes the entire splined hub and puts it on one single disk, then floats the second disk on a set of much larger/beefier splines to prevent failure, while hopefully reducing harmonic/chatter issues. The splined hub is approximately 3.00" and is 39-spline for engagement of the second disk, whereas the old version is like any other Mitsubishi (Ford 20-spline) is a 7/8" 20-spline engagement hub. The clutch disk hub is also much stronger by the fact it is now using 12 rivets instead of the 8 rivets used on the current production version. It also should have a slightly lower moment of inertia as more of its weight is centered at its radial axis than before.

What we came up with is the design shown below (all Quarter Master's idea for design), for OUR APPLICATION!

The entire clutch assembly and flywheel assembled weight is right around 18 pounds!


Please understand, this is a COMPLETE PROTOTYPE clutch/hub design, and has never been used on a DSM utilizing a Gear-Drive Hub!!! This is "THE" TEST version!

I will be installing this clutch in time for the 2009 race season on a completely new race engine and turbo setup that is beginning to go together as we speak. The new HP goal is 900+AWHP, and 750 torque on a 7-BOLT 2.3L aluminum rod/ custom piston/stock crank. I have not purchased the turbocharger yet, but that is the easy part.

The goal is to put down as close to an 8.99 as possible in my street car. I still need to finish my roll cage add-on's along with the parachute mount, and window net in order to be compliant with all NHRA safety regulations. This will happen after the engine is back in the car though. If I cannot break into the 8's, I will not feel bad, since I will have already acheived so much on the 7-bolt 4G63 engine; let alone for an all-turbo street car.

So on to the show, and THANK YOU QUARTER MASTER CLUTCH!!!!!! This company has excellent customer service and has the ability to tailor a custom clutch to the user's needs!

When the dyno-tuning begins on this new clutch/engine/turbo setup, I will keep everyone in the loop as to its clutch characteristics, chatter, engagement, capacity, etc. Dyno Tuning is expected to start around August 2009 (EDITED TIMEFRAME FOR ACCURACY).



I have attached several photos for you all to see:

 

[twicks69]

More pictures!

 

[twicks69]

Here is a picture of the current clutch pack design for reference:

The disks shown are the higher HP capable, heat-treated version from Quarter Master.

 

[andy4g63]

That is good to hear, Tim. Clutch looks awesome. Are these sintered iron disks?What is the torque rating on this clutch.


P.S. Which turbo you leaning towards to??? Just curious.

 

[twicks69]

That is good to hear, Tim. Clutch looks awesome. Are these sintered iron disks?What is the torque rating on this clutch.


P.S. Which turbo you leaning towards to??? Just curious.

Yes, they are the sintered iron disks, just like what they normally use for the standard application.

As for the torque rating, there isn't one currently. I would expect that they would tell you it is around 600 Tq, but we all know that ratings aren't the clutch disk's actual capacity.

Since the old ones easily held up (friction material wise) to 900+TQ at the flywheel without failures or slipping, or overheating. The friction disk thickness is 0.250" per disk, and the old set (the ones that sheared the hub splines) were 0.244" thick after 3 years of use and abuse!


As for turbos, it will be something in the compressor exducer size of 100+mm.

 

[andy4g63]

Got it. Thanks. Can't wait to see the results you'll put in.

 

[projecTSI]

Very impressive Tim. Can't wait to see how it works out for you!

 

[turbosax2]

Why didn't you go with the 4.5" triple Carbon-V setup?

 

[twicks69]

Why didn't you go with the 4.5" triple Carbon-V setup?

Well, the key reason was price.

The 4.5" triple carbon-V clutch with custom button flywheel (or flexplate with ring gear) is around $6500+. The clutch rebuild is also around $5500 when it requires it. As well, the carbon clutch requires constant shimming to keep it within spec. It is a very high maintenence clutch.

This clutch rebuild costs less than $400 for new disks, floaters and pressure plate spring/hardware. As well, it is direct bolt-in, and doesn't require any custom stuff other than a machined clutch fork and automatic flex plate bolts to attach the flywheel. It should also have a much better service life. As well, this clutch is around 6 times cheaper than the carbon setup.

 

[turbosax2]

So this clutch will be priced about the same as the current QM twin disk? By "machined clutch fork" do you mean modifying the stock one or having to make a completely new one?

 

[twicks69]

As for pricing, I have no idea -- this is a prototype clutch.

The clutch fork just requires a tiny bit of grinding to clear the pressure plate cover. It is nothing special to do.

 

[Slippi84]

How much of a problem was it really with the input shaft splines shearing off. Were you a isolated case or have there been reported others that have had this happen. I ask because, while we obviously don't know the set price yet, if the PTT and Quartermasters out now are both running on several 7-800whp cars right now without any chronic problems most dsm member won't spring for this design even though it's obviously more advanced and a better solution. Kinda the old "if it aint broke"

 

[twicks69]

Well, I am not the only one that had sheared the splines off the normal disks. That is the reason that the heat treated hub versions were brought about. To what I understand, I was the highest torque car that these stock disks lived on before failing -- at least from Adam at Devo, and from Jeff at Quarter Master. The heat treated hub clutch disks don't fix the underlying problem, it is just a bandage fix. The problem is that there is not enough of the input shaft being engaged to properly take the torque transfer without distorting or failing with the original design.

In this circumstance, it is a completely new design which weighs less, has lower moment of inertia, and is much stronger in design. It also more than doubles its engagement area on the input shaft, while offering the potential for less clutch chatter and will offer the ability to completely remove the possibility of twisting your input shaft splines along with shearing the clutch splines off.

It is completely a WIN-WIN scenario.

As well, these clutch disks could be a full replacement for your current clutch disks. The pressure plate, fulcrum and floaters are still the standard off-the-shelf parts. The clutch disk hub design is the ground-breaking part of the overall design.

 

[Slippi84]

Well, I am not the only one that had sheared the splines off the normal disks. That is the reason that the heat treated hub versions were brought about.

In this circumstance, it is a completely new design which weighs less, has lower moment of inertia, and is much stronger in design and more than doubles its engagement area on the input shaft, while offering the potential for less clutch chatter and will offer the ability to completely end the possibility of twisting your input shaft splines along with shearing the clutch splines off.

It is completely a WIN-WIN scenario.

As well, these clutch disks could be a full replacement for your current clutch disks. The pressure plate, fulcrum and floaters are still the standard off-the-shelf parts. The clutch disk hub design is the ground-breaking part of the overall design.

Nuff said. Of course this is a prototype but is this something that will be around like months from now or should we not hold our breath?

 

[twicks69]

Nuff said. Of course this is a prototype but is this something that will be around like months from now or should we not hold our breath?

Well, I will be the first person to test this clutch out, and I am expecting to do so in April.

My engine is at the machine shop getting prepared for a Groden/Ross setup, and we are only waiting on the custom pistons to be made and shipped.

Other than that, I just need to purchase a new turbo, which is no biggie.


The goal is to get the car up and running and then directly bring it to the dyno for testing the clutch (along with the new setup). I will be contacting Quarter Master when the test results are in, and then they will go from there. If it works great, I would think that they would put it as a production design.

In this circumstance, it took Quarter Master less than 4 weeks to put the design into the prototype piece I now have. This is extremely fast considering the holidays that were during this period of time, and the fact that it took much more time to receive the original clutch in 2005 when it was a production-level part.

 

[Black94DSM]

Subscribed!

I'm looking forward to seeing how this turns out. Keep up the good work Tim, it's nice seeing products are still being made for our cars.

 

[twicks69]

Jeff Neal from Quarter Master called me up yesterday to make sure I received the clutch, and wanted me to do my dyno-testing and run some of the season on it, and then send it back to him for analysis along with my comments. After that it would be rebuilt for me, and any revisions that need to be made can then be done.

Again, awesome service! It is an honor to work with a company willing to do something like this for a one-man-show race car, as their company along with nearly every other company out there only sponsor or help out professional race teams.

He sent me 4 stickers as well, and they will definitely be installed on the Eclipse!

I absolutely cannot wait to get it on the dyno!

Custom pistons have been ordered, and that is all we are currently waiting on for the engine to be assembled. From there, I will receive it back from my machinist and will do the finish assembly and installation.

As well, if I do go with a GT42R-framed turbo, I will just need to make up a new downpipe and lower intercooler pipe. I might need to do a bit of other custom fab stuff, but no biggie. As of right now, April sounds like it will work out as the time for dyno-tuning and street/race testing this new clutch!

 

[turbotalon1g]

Good luck to you Tim.

Also while you thank QM, thanks to you for keeping good people in the DSM game and for not giving up, you are an inspiration.

PS, thanks for the advice on the transmission.

 

[twicks69]

Good luck to you Tim.

Also while you thank QM, thanks to you for keeping good people in the DSM game and for not giving up, you are an inspiration.

PS, thanks for the advice on the transmission.

Thank you!

I will do my best to continue supporting the DSM community for the years to come!

 

[talondsp1]

Subscribed...

 

[DSM_PWR]

Hmm... decisions, decisions...

My build is schedueled to be finished late May through Early July and i was going to go with the original QM Twin Disk but now seeing as this new prototype should be stronger...

I may just have to put off the block till i see these results (since ill need the clutch for full balancing)

Dangit Tim now i gotta wait longer

 

[twicks69]

you don't need to wait for the clutch for balancing; it comes fully balanced from quarter master. If anything, wait for the clutch, or pick up the standard unit. I didn't have any problems with it until I got to 700 torque range.

 

[Slippi84]

you don't need to wait for the clutch for balancing; it comes fully balanced from quarter master. If anything, wait for the clutch, or pick up the standard unit. I didn't have any problems with it until I got to 700 torque range.

I'm probably gonna pick up a regular unit and then replace the disk when these come out.

 

[twicks69]

I'm probably gonna pick up a regular unit and then replace the disk when these come out.

Exactly my point. The disks are the only different component between the off-the-shelf unit and this prototype unit. The pressure plate, spring, fulcrum floater and standard floater and flywheel are the exact same parts. They will be fully interchangable disks with the standard unit.

 

[DSM_PWR]

Ah ok...

Hm.. my machine shop recommended to bring in the clutch/flywheel to balance the rotary assembly?

I dont mind waiting since the car wont be running anytime soon and im one of those "Buy once/not twice" type of people