...stinkin clutch

[Andrew Scott]

The more metal a clutch has in it, the less it will slip, the more break-out power it will have and the harder it will engage, and the worse it'll be on the street. ie. on off switch. This includes copper, iron, etc

The more organic material a clutch has, the smoother it'll engage, but it'll slip more. This includes kevlar, etc.

Carbon holds great and engages smooth, but is super expensive.

Things like multiple discs, marcel springs and sprung hubs will make it engage easier.

I had a CFDF and ran alot of power through it. You just gotta be careful not to launch over and over with it without taking a break. At the track you have a super long wait between runs anyway, so not a big deal.

[Trev_Scott]

Im going to be trying sbr's 3500 Heavy Duty Clutch Kit with prob an act exact flywheel combo, but might switch to a fidanza flywheel not too sure yet. If you go to dsmtuners and search for any clutch that your interested in, you will find tons of reviews. Hope this helps.

After talking to sbr i decided to not buy this clutch. I would highly NOT recomend this as of right now.
http://www.labattz.com/phpBB2/viewtopic.php?t=14860

[Richard Steger]

I've used Dsm Tuners site alot but never registered for the forum. Now I am.  Sure sounds like ACT had alot of spring failures for awhile. Some with Slowboy/Kinetic/Competition Clutch too. Spring failures aside, it sounds like the ACT2600 is too stiff in the pedal for my liking and the 2100 too weak for launching, slipping, etc.  So no ACT for me.  The CFDF actually sounds good with the one caution that you let it cool for 1/2 hour between launches.  I'm leaning towards South Bend DXD and Unorthodox racing discs and pressure plates, but the Unorthodox is 50% more.  So I guess when cost is an object my choice is between the CFDF and South Bend.  Here is the reply from South Bend regarding my inquiry for a light pedal, good daily drivability and heavy launch abuse clutch for 300 lb/ft of wheel torque:

 "I recommend using our K 536 SS OFE.  This clutch will give you both good streetability and durability at the track.  It is a full face clutch and will not groove the flywheel like the puck designs.
 Your cost for the clutch with a Fidanza L/W flywheel is $770. If you buy the combo I will cryo for free. "  http://www.dxdracingclutches.com/home.html

By the way, I noticed that Shepracing.com has ACT on it's page, so I emailed them regarding the difference between aluminum and steel flywheels and John Sheperd replied: "I feel there is less maintenance with the 1 piece flywheel.  
Thanks
John Shepherd"
I guess that means he likes ACT's one piece chromoly flywheel, which has integrated ring gear and pressure plate surface.

Road Race Engineering says on their tech page regarding aluminum flywheels :  "... stock flywheel weighs in at about 19 lbs. Our lightened stock ones are 14 to 14.5 lbs. That 5 lbs alone is enough to feel a difference. Aluminum flywheels weigh 9 lbs for DSMs. Now you are talking. You are using less power to spin the flywheel and now have more power available to move your car down the road.
 Lots of people freak out about any "theoretical" negative drivability issues with lightened flywheels. They are wrong, it's all good. They are not too light for street use, they won't break apart, they are stepped correctly for ACT and CFDF clutches,  On a 80 hp honda you could go too light, but not on anything with enough power to pull the skin off pudding. You will have to compensate a little in your launching technique, a little higher launch rpm will be necessary. Your shifts will be better with the engine rpm now better matching the next gear. These are SFI certified."

Seems like you can find support for any combo if you look hard enough.

[John Hartman]

that clutch sounds interesting for sure.

as for the flywheel, well Shep is making ALOT of power and he really abuses his.  Normal fast street cars are different.

As for the CFDF, Lowell has done repeated passes with fast cars.  As have I, after talking to him last time at the track.  He has hot lapped several CFDF clutches, but ALWAYS with aluminum flywheels.

They are only supposed to be good for 375 lbs/ft to the wheels however, so if you are actually going to make alot more than that, maybe choose accordingly.

[Mitch Delmer]

Since I am a 5 speed now I want to contribute...

I love my CFDF, it will smoke all four tires anytime I wish (including a couple of budweiser induced reverse to firsts....  :laugh: )  
But really, it is a good clutch.  When I grab second gear it slips a little, but I think this is actually better than a on/off type of clutch as it saves the driveline and it doesn't lose traction and smoke the tires.  It does however like at least 5 minutes between launches or it will stink something fierce....for a couple of hours..  Pedal feel is better yet, I think it is lighter than the stock clutch that I had in there before.

Being also that I have put together a few cars for other guys up here and have installed ACT 2100's, 2600's, and a Kinetic six puck, they all rock, but for everyday driveability I personally will use the CFDF until it wont hold the power I am putting to the road.  The 2100 would be runner up If I had to choose, and then the 2600 although its pedal is really stiff and would get real annoying after a week or two.  The kinetic six puck is just sick, but is on or off, if you try to modulate it your car will chatter and shake until you jus put the clutch in and try again...no fun at all on the street and especially starting on a hill.

And as far a break in period, I break my stuff in how I am gonna drive it...Hard.  No ill effects yet. But I bet that if you let the clutch seat in for 500 kms it would work even better, but I dont have the willpower.

[Andrew Scott]

The CFDF clutches need a pretty good break in... if you don't seat it nicely, it'll glaze badly, like all organic discs. The CFDF has a metal component that isn't quite as suceptable to glazing, which makes it less sensative to a rough break in, but every bit helps right?