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Correcting improper clutch geometry

103K views 195 replies 81 participants last post by  Bjorn  
#1 ·
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.
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But they use different discs which are also from Exedy.

The ACT disc (exedy disc part# HD510D)
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The Centerforce disc(exedy disc part# HD511D)
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The CM FX400 disc(made by CM's own supplier supposedly(I suspect Exedy))
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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 of the stage3-4 clutchs and places the engagement point up off the floor.
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#3 ·
has any1 else tried this
 
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#10 ·
since were on the topic of clutch. I have vibration with the exedy stage 2 clutch when you press the clutch and let go real fast..

anyone have the same problem..?
 
#11 ·
The "washer fix" its a fix also for the new civic si and evo X when they install a new act clutch due to improper geometry.
bossman: a bit of vibration is normal with aftermarket clutch. I dont know what kind of vibration you get, but when I did my friend's rsx with a CM stg4 its a bitch to DD it.
 
#12 ·
Do I have to do this if I run a CM or CC stage 2? I know you listed stage 3 and up, but I'm assuming that it is better safe than sorry.
 
#18 ·
I was curious to know how far off the floor a washer like this would add? Is it just enough or is it like half the travel? I have the Prolite flywheel and the AR1-XTSS pressure plate. ACT told me to adjust the master cylinder rod connecting to the pedal and the MS blew about a month later. Another person told me the pressure plate is too stiff for the MS and thats why it blew. I think it was because the rod was adjusted to the max and the system was preloaded. The vehicle is a 07 Si.
 
#22 ·
Wish I would have seen this a couple weeks ago when I helped my buddy put his clutch in looks like we'll be pulling it back out!

He's had 2 masters and keeps blowing them out!
Or you can buy an adjustable slave cylinder from me.
 
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#24 ·
I wished the washer trick worked on K20Z3 equipped vehicles, sadly it's not enough. But this set back enabled me to create a new part to benefit the K Series community.
 
#31 ·
It wouldn't hurt though I doubt you would need it.
 
#38 ·
Ok, I just installed a Comp clutches stage 4 and its kind of hard getting it in 2nd gear. its a K20R with a rsx-s CMC, my release point is way too close to the floor and the pedal is adjusted pretty far out so I'm guessing its got to do something with the clutch. any help would be nice.

oh and also if I do this washer trick, you think it would make my release point a bit higher? thanks