Correcting clutch throwout geometry on stg3+

[talonXracer]

Resurfaced flywheels FTL with stage3-4 clutchs.
You do know that Exedy/Daiken manufactur ALMOST all the clutchs other than twin discs that are used in the Kseries trans.

The stage 3-4 clutchs from ACT, Centerforce, Exedy and Clutchmasters, all use the SAME pressure plate except for the exterior paint.
ACT hdss, Centerforce, FX400 pressure plates.
http://i54.photobucket.com/albums/g96/talonxracer/IMG_0592.jpg

But they use different discs which are also from Exedy.

The ACT disc (exedy disc part# HD510D)
http://i54.photobucket.com/albums/g96/talonxracer/IMG_0589.jpg
The Centerforce disc(exedy disc part# HD511D)
http://i54.photobucket.com/albums/g96/talonxracer/IMG_0588.jpg
The CM FX400 disc(made by CM's own supplier supposedly(I suspect Exedy))
http://i54.photobucket.com/albums/g96/talonxracer/IMG_0590.jpg


These pressure plates are a little on the "short side" for the installed height when compared to a stock dimension pressure plate. This shorter height is compensated for by the hydraulic system, but it places the throwout arm and slave cylinder close to half travel already. As you step on the clutch pedal the slave starts moving as well, but before the CMC has reached max travel the slave has But because the CMC is traveling it continues to pressurize the system causing the hydraulic failures seen.


This can be fixed by adding a washer between the throwout arm pivot ball stud and the clutch case correcting the faulty geometry that the stage3-4 clutchs creates and places the engagement point of the clutch pedal up off the floor.
http://i54.photobucket.com/albums/g96/talonxracer/IMG_0593.jpg

[Jpax]

Thats one way to recycle. lol good info

[jimmyjames]

2 questions.
What's wrong exactly with a resurfaced flywheel?
Does this fix apply to all stg 3+ clutches (i.e. stg 4 competition clutch)?

[talonXracer]

Honda specifically states not to resurface the flywheel in the Helms. The reason for this is that it places the pressure plate closer to the engine and further from the throwout bearing resting position. Most stage 3-4 clutchs suffer from basically the same thing(their installed height is lower, just like resurfacing the fly with a stock pressure plate.) And when you resurface the fly and use a stage 3-4 pressure plate the installed height is even LOWER, this places more of the slave cylinders pushrod out of the slave, reducing the amount of throw available. Adding the washer behind the pivot point justs compensates for this lower installed height.

[03Si757]

I have a RED Clutchnet Pressure Plate and a Resurfaced flywheel, so I went ahead and did this trick, seems to work GREAT!

[gtimportfanatic]

thinking i shoulda done this

[EP3Casas]

wats happening with ur clutch?

[gtimportfanatic]

wats happening with ur clutch?

4 months later lol...

my clutch slips alot.. esp when i was boosted.. second gear would slip hard esp at the drag strip or if i was doin a hard pull.. u live n u learn

[Kerby]

wondering how much it would cost to manufacturer a bolt that would do the exact same thing... minus the washer to give the extra length to correct the geometry, but also have enough meat for the threads to make contact.

what's the thickness of the washer most people are using to correct the geometry?

[talonXracer]

I used a standard washer out of the parts bin, 1/16th"-3/32nd", a machined and hardened pivot costs considerably more than a washer.....

[Kerby]

a machined and hardened pivot costs considerably more than a washer.....

Not if you do a run. I'm sure alot of DC/EP owners are running stage 3 clutches. I'll look into it. I used to work for a machine shop. they have a threading division attached to the shop. so everything will be done inhouse, minus the heat treament. seeing how this is for an automotive application, the clearences are pretty much wide open.

[EP3Casas]

u have plenty of threads left even with the washer. at 1 point i had 2 washers on mine. did nothing for the problem but still had plenty of threads

[talonXracer]

Not if you do a run. I'm sure alot of DC/EP owners are running stage 3 clutches. I'll look into it. I used to work for a machine shop. they have a threading division attached to the shop. so everything will be done inhouse, minus the heat treament. seeing how this is for an automotive application, the clearences are pretty much wide open.

I HIGHLY doubt that you can produce a pivot ball for under .03$, I also worked at a machine shop, one that I am a part owner of.

I know I would not purchase one when a washer works. besides the reason for needing the washer is that very attitude of it "only being a automotive application" so the clearances are wide open.

[RedSiBaron]

those sprung clutch disks looks identical to the oem one i just put in, including that brand logo...from what i understand exedy is an oem supplier anyway...

[D3xn2o]

those sprung clutch disks looks identical to the oem one i just put in, including that brand logo...from what i understand exedy is an oem supplier anyway...

Indeed they are for most companies

[bchaney]

Shouldn't the flywheel always be resurfaced when installing a new clutch?

I'm pretty sure the clutch manufacturer recommends it. Is Honda/Helms suggesting you get a new flywheel every time you replace a clutch?

[RedSiBaron]

Shouldn't the flywheel always be resurfaced when installing a new clutch?

I'm pretty sure the clutch manufacturer recommends it. Is Honda/Helms suggesting you get a new flywheel every time you replace a clutch?

no the honda manual doesnt say replace the flywheel, it says to check the thickness for excessive wear, if below a certain thickness it is considered "unsafe" and should be replaced...similiar to brake disks...

when i did my clutch the flywheel was easily still within specs and it has 95k on it...

[talonXracer]

those sprung clutch disks looks identical to the oem one i just put in, including that brand logo...from what i understand exedy is an oem supplier anyway...


Indeed they are for most companies

Exedy/Daikin makes the majority of OEM clutches as well as probably 90% of the aftermarket.

The Helms manual states to check the thickness of the flywheel and surface deflection, it also states that the flywheel CANNOT be turned, it must be replaced. The reason for this is the same as to why the aftermarket clutches have issues, their short installed height.

But I have turned many a Kseries flywheel and simply installed a shim/washer under the pivot ball

[bchaney]

I have a Competetion Stg2 and a resurfaced a2 fly for my build. Should I install the washer if the fly is still in spec? How bout if its undersize?

[jones02]

what if you get the stage 4 CC clutch and fly would you sitll have to add the washer or is it good when you have both?

[talonXracer]

I have a Competetion Stg2 and a resurfaced a2 fly for my build. Should I install the washer if the fly is still in spec? How bout if its undersize?


A resurfaced fly will not be within spec, any wear or resurfacing will put the fly out of spec, they are considered a replaceble part just like the rear brake rotors.


what if you get the stage 4 CC clutch and fly would you sitll have to add the washer or is it good when you have both?

You will need to try the clutch pedal, if the engagement point is close to the floor a washer is needed.(this can be checked prior to install)

[rd02SiR]

This has to be done with the tranny out eh?

I'm getting an ACT flywheel with a stage 3 pressure plate. Will I need to get the shop to do this before completing the install? Or will it be fine since the flywheel is not resurfaced.