nah2b props for taking the time to measure everything. Do you lift off the gas when you shift?

 

what was the step height of the friction plate in relation to the flywheel? just trying to see if the numbers jive on my end... thanks!

 

im not to sure i would have to call the shop im not the one working on it

 

yes i do lift.

i would never wot shift my trans w/ a single disk clutch, thats just asking for problems.

i want to step up to the tilton twin disk setup for this reason, i hope to be wot shifting next season.

 

Hey Randy, would you say that the friction plate on the flywheel looks to be about .250"? from your measurement of .112" and the depth of the mating surface at .140" it would seem that .250" +- .002" thickness for the friction plate would be the norm. I'm just trying to get to the root of the problem by process of elimination. Thanks!

 

btw, i measured my throwout bearing today and it is .950" thick.

Honestly i dont believe the bearing would make a difference and heres why...

the bearing and fork are going to sit wherever they are comfortable against the pp, the slave is not putting ANY pressure against the fork until the pedal is pushed in correct?

when you push the clutch pedal, the master cylinder is going to push x amount of fluid and extend the slave which inturn extends the fork and bearing, follow me so far?

well lets say you use a thicker or thinner bearing. this will only result in compressing or extending the slave while the bearing and fork are sitting where they are comfortable against the pp.

when you push the pedal, the master cylinder is still pushing the same x amount of fluid to the slave which inturn pushes the fork the same distance as before and in turn pushes the bearing into the pp the same distance as before.

as long as the bearing isnt outrageously over or under sized causing the slave to bind or come apart, which would be obvious.

 

sorry, im a little slow

if im understanding you correctly, you are asking how thick the friction disk is by itself?

good question, i havent removed the friction disk from the flywheel so im afraid i couldnt confirm the thickness of the friction disk or the depth of the surface underneath of it compared to the pp mating surface?

 

If the friction plate is about .010" thicker than whats called out, coupled by an out of spec pressure plate thickness. Would everyone agree that is enough to cause the shifting problems? Or would that be a question for the clutch manufacturers?

 

i bought one of the very 1st evo h2b kits... 1st one sent to New Zealand

and the car has developed the same problem!

my clutch slave in my old h2b looks EXACTLY like this


dosnt engage untill the last few mm of releasing the clutch pedal, and im sure its just slipping at higher RPM!!!

 

i win!!!

 

Basicly the last 2-5cm clutch pedal Americ_Ian is talking about its stupid >_<

 

i had a chance to measure a couple stock oem b series flywheels, here are the results:









as you can see the oem b series flywheels have the same step height as my evo flywheel. i would be very curious for those of you who are having problems to measure your evo flywheels and see if they have this proper step height.

CHECK YOUR FLYWHEELS step height should be .112" or 2.85mm


other than that the only causes i can see being the problem are: mismatching clutch disk/pressure plate, loss of hydro pressure (leaking slave or master), internal transmission damage, bent or improper shift linkage, improperly installed clutch disk/bearing/fork

and to those of you using a Competition single disk clutch, these clutches are KNOWN for not allowing shifts at high rpm and for allowing the car to "creep". if you are certain everything else is in proper working order, i would suggest swapping out the comp clutch for an exedy clutch simply because they are KNOWN to work as good as oem

 

 

anyone have any updates?

 

I measured the step on a new B series Fidanza and got .109 or 2.769mm

 

turboedsupdup what's the update on this?

 

Sorry guys had a couple set backs and my car got put on the backburner. But i am dropping the tranny this week and should have a answer a couple days after that

 

what are you planning on doing

 

Sending my whole setup to action clutch since the evo kit was designed around there kit hopefully they will find some difference. I will be sinding them everything including fork and bearing just to rule everything out. I will also probably be switching clutches just not sure which one im going to go with. I want something a little smoother engaging then my CC stage 4 6 puck. But it has to be able to take some slick abuse at the track

 

have you measured the step height on your evo flywheel yet?

 

No i havent, like i said i have been slacking off and havent got it dropped yet. I will this week though and have some results

 

just make sure to properly measure it before you send everything away. im curious to see if some of the flywheels may have an improper step height which is causing all these problems.

 

So what happens to that measurement when the flywheel gets resurfaced? material taken off....

TO bearing.

 

Ok i got my tranny out and so far the only thing i can see were the springs on my srung hub were making contact with the evo flywheel. Im glad i got this clutch out before it broke one of those springs. I will be taking all the measurements tomorrow at work before i send it out and will hopefully be posting pics of them just as Randy did

 

something is very wrong w/ your setup if those springs are contacting the flywheel.

are you sure the disk wasnt installed backwards? it sounds dumb, but it does fit backwards w/ the deep offset of the h2b flywheel.