Can you resurface the evo original flywheel - good idea or bad? Do you always need to replace the flywheel on a clutch install? Can you resurface aftermarket flywheels? Thanks. (My car has 11,000 miles and an EXEDY hyper single. I bought it used with this clutch.)

 

In my DSMs, I would just resurface the stock flywheel. When I replaced my Evo clutch with an ACT, the master tech told me that the stock Evo flywheel is not supposed to be resurfaced, because it is not a two-step, and Mitsu does not provide a resurfacing spec. It can be done, and I believe people DO IT, but I was convinced not to by this master tech who we all respect greatly in the DC area as the primary person to go to for repairs. I replaced my flywheel instead of resurfacing it so as not to worry about future clutch engagement dynamics being thrown off or sacrificed. The end result is that I have a much more powerful clutch with no noticeable change in engagement point (good pedal adjustment) and with no change in driveability from stock other than a stronger grab.

I don't know about resurfacing aftermarket lightened flywheels...I would guess you're not supposed to, but I'm sure others can chime in who have direct experience with such things.

 

Unless its totally warped then yes you may easily resurface your stock flywheel with zero issues to worry about.

 

WORKS recommends replacing the flywheel as well. Most of the EVOs coming into our shop with slipping clutches end up being a warped flywheel. Resurfacing it removes material and makes it more prone to warping in the future. Our chromoly Spin flywheel is resurfaceable while our aluminum Spin flywheel has a replaceable friction disc.

 

RRE resurfaced mine. 4,000 miles and no problems so far.

 

i resurfaced mine, but it didnt have any heat cracks, or severe blueing..

 

I replaced mine with a new stock one. When i pulled my clutch after 14k miles, my clutch still looked pretty good, but my flywheel was beat to ****. didn't wanna take a chance on resurfacing it and using it with a new clutch.....

 

Exactly my experience: the clutch disk had plenty of material left, but the flywheel was a mirror with SEVERE hot spots all over it. Since you can't determine the depth of the hot spots before cutting, then if you decide to resurface, you could end up going too low for the flywheel to be reusable, since you have to go to the base of the deepest hot spot.

I would imagine that on a clutch replacement in which the original setup was not abused and is just being replaced as a precaution, then the stock flywheel could probably be resurfaced without issue, but I don't see how it would be recommended if there is any signifcant resurfacing done, since it's not a two-step. The moment you resurface it, the engagement point goes below the flywheel housing. The flywheel surface is flush with the housing (or whatever you call the outer surace that doesn't touch the clutch disk), so there is no depth to sacrifice.

Atlvalet says his has been fine, but it would help to know how many millimeters they cut off the original flywheel...

 

I could find out.

 

What he said.

 

Ditto! You other guys are trying to think too hard or you are superstitious.

FYI: Any hot spots on the flywheel are usually hard, far deeper than what you can resurface out. The clutch doesnt care hard from soft really, only high and low to there are no problems with hard spots until they become high or low spots. On grey iron castings you have to watch it, but since the stock EVO flywheel is not grey iron, you are pretty safe that it won't blow up like the typical flywheel can when it gets cracked. I have seen some pretty ugly flywheels that are no problem to resurface so don't be alarmed by how it looks. Put a straight edge on the clutch surface and check how warped it is. If it is less than .020", then you are pretty safe on the EVO. If it's cracked, throw it away. If it is smooth with no high spots and it is warped less than .005", I doubt if you would notice any difference if you did resurface it.

The few thousanths of material you are going to take off if you resurface a flywheel isn't going to have a significant impact on operation (unless the machine shop screws up). You would have far more impact on warpage from an extra 1/2 second of slipping than you would by resurfacing the flywheel. The driver is the single biggest variable in how hot the clutch and flywheel is going to get. So if you really want to prevent warpage, don't worry about the flywheel and watch how you drive instead.

And this is coming from someone who manufactures and sells flywheels. We make a lot more money selling flywheels than telling people to resurface theirs or to drive carefully so not to burn one up. I have seen some pretty bad resurface jobs though, so beware. Someone mentioned RRE... they are pretty picky and I have seen their work, so I would trust them for sure. We also do it and we include dynamic balancing, but we don't really advertise the service. We would rather build new clutches than do rebuiliding, but we have the right equipment.

 

This is a little off topic, but since Dirk has responded...

What's the best thing to do after you severly burn your clutch? Run it for awhile? Turn it off and let things cool down? I think Shiv took off the 5,000rpm rev limit. I was talking to my friend for a second(kinda not paying attention) and then realized that I had let the clutch out a bit and was slipping the clutch at about 6,000 without realizing it. I disengaged the clutch immediately, but man did it smell bad. There seems to be no problem (go ACT) but was just curious what the best procedure was.

 

When you oveheat a clutch what you are smelling the resin in the friction material being melted. What happens is that the resin becomes more like a lubricant than a binder until it is allowed to cool back down. So you definitely want to let it cool before going WOT again. Keep in mind that whatever heat goes into the clutch disc also goes into the pressure plate and flywheel so warpage is a concern whenever you really smell clutch.

The disc also loses a layer of material each time you cook it so it shortens the life of the clutch. When you burn off the nice smooth lapped-in surface, you should go through another break in procedure to get it lapped in before aggressive driving.

 

re-surfaced flywheel, done by master tech, evo 7 service manager, mitsubishi.

with act clutch.

i have about 15,000 miles on it, showing a bit of wear, but still going straight, no such problems whatsoever. Engagement point went up just a little bit.

That's with about 50+ launches at the drag strip around 6k rpm. And yes if you do the launch right, you could save your clutch from slipping for a long time.

took me a stock clutch to figure that out.

 

What is the direct reason for this? I assume this is a bad thing. Is this something that can be adjusted? I noticed the same on mine aswell .