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Old 03-22-2007, 09:25 PM   #1
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Default ACT 1.8 HD is in

I got about 35 miles on my new clutch (ACT HD 1.8 w Organic Disc) and flywheel (lightened oem 1.8).

Okay, now when people say pedal pressure is *slightly* more than stock, they're full of ****. I'd call effort 3x stock. I compared with a 90 miata with its stock clutch. I had to move my seat 2 notches forward to deal with it. I even checked the box to make sure they didn't accidentally send me the XT. Also, I asked my woman to start the car and I heard her groan when she pushed the pedal in. (no, I didn't install the clip).

All the magic does happen close to the floor. Engagement is sudden. Not quite digital, but not far off either.

Starting from a stop is more difficult, between the increased pedal effort and suddenness of engagement. However, shifting between gears is very pleasant with the lighter flywheel. I found that I could make perfectly smooth 2-3 and 3-4 shifts that wouldn't spill a full glass of water.

Can't comment as to how it holds under torque, but it damn sure grabs positively.

I'll take some pics of how burned up my old clutch was and post them sometime later.
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Old 03-22-2007, 09:30 PM   #2
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I installed mine over xmas break. After 1500 or so miles, the engagement has come close, if not exactly to, stock height. I've either gotten stronger or the pedal effort has reduced to slightly above stock as well.
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Old 03-22-2007, 09:41 PM   #3
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Interesting, hopefully over time I'll get used to it and/or the clutch will get a bit more civil like yours.

Good to know, thanks.
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Old 03-23-2007, 05:00 PM   #4
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after it brakes in it isnt much worse then stock. also override your clutch netrual switch for when you turn on the car so you don't pwn your throw out bearing.
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Old 03-23-2007, 05:02 PM   #5
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I drove my roommates '90 last night, he has a exedy(?) replacement clutch and the 8 lb fidanza. I just about pushed his clutch pedal through the floor there is so much difference between mine and his. I know mine is broke in so I assume that it is the XT seeing how the clutch was in it when I bought the car. The engagement is so much different. His is more near the top whereas mine is in the last 4" on pedal compression. I like mine better.
To override my clutch switch i just cut the wires and wire-nut'd them together.
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Old 03-23-2007, 05:21 PM   #6
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I have the override clip; it came with the clutch kit from FM. I didn't use it because it makes it easier for the woman to run into another car or vehicle if she had to start the miata. I always leave the miata in gear when I park. When's the last time you heard about a throw out bearing failure? I'm sure the heavier pp isn't the best thing in the world for the thrust bearing, but I'm not worried about it.

Last edited by Ben; 03-23-2007 at 06:43 PM.
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Old 03-23-2007, 05:29 PM   #7
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the intent is to save wear on the thrust bearing at startup when it's not lubricated
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Old 03-23-2007, 05:35 PM   #8
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Quote:
Originally Posted by m2cupcar View Post
the intent is to save wear on the thrust bearing at startup when it's not lubricated
Please explain this.
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Old 03-23-2007, 06:06 PM   #9
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with the clutch in, the force of the pressure plate is essentially pushing on the flywheel (the crank).

since you gotta hold the clutch in to start the car, you're axially loading the thrust bearing before oil circulates.

FM makes a brackey to hold the switch closed because they believe it's bad for engine life to load the thrust bearing at startup.
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Old 03-23-2007, 06:10 PM   #10
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Since it takes more force to disengage the clutch, you are applying more forward force on the thrust bearing. Since it is not lubricated during startup, wear will be accelerated compared to the force of a stock clutch.

While it holds true in theory, I have yet to see any proof that the accelerated wear is enough to measurablely shorten the life to the bearing. It makes sense that it happens, but there is little proof of the real effects.

One real effect is my wife accidentally driving the car into the wall on startup, so no bypass for me.
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Old 03-23-2007, 06:43 PM   #11
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Quote:
Originally Posted by mschlang View Post
While it holds true in theory, I have yet to see any proof that the accelerated wear is enough to measurablely shorten the life to the bearing. It makes sense that it happens, but there is little proof of the real effects.

One real effect is my wife accidentally driving the car into the wall on startup, so no bypass for me.
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Old 03-25-2007, 06:39 AM   #12
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From what my Powertrains teacha said. 1) no lube on the bearing 2) it is a constant running bearing so it is always is spinning cept for at start up and now you have to apply so much more force.

but yeah if others drive the car i'd not have it bypassed but i figure cus im the only one who drives it bettah safe then sorry.

Also i have the HD kit and after brake in you might have to adjust peddal height. Called ACT on this one and they confirmed it with the HD clutch the engage point should still be the same just a bit more force to get the pedal down. The spec's I found on Micthel On Demand where the same ones ACT gave me something like .5in of freeplay at the top and like 1-2 inches of space from the pedal and the floor when it is all the way down.
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Old 04-04-2007, 06:02 PM   #13
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250 miles on it now. I'm getting used to it, and it's really grown on me. I gave it a couple psi of boost a few times. Figure it's rated for 230+ ft lbs, and I'm not putting anything near that on it at 2 psi.

The lighter flywheel is nice. I'm glad I did it.
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Old 04-05-2007, 12:39 AM   #14
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i dunno man, my 1.6 HD feels exactly the same, too light.

I driven in a few with heavier plates and it feels better imho....my guess is you've never driven a mustang 5.0
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Old 04-05-2007, 12:52 AM   #15
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That's interesting. The 1.8 HD definitely ain't light.

Yes I have driven a few Mustangs, including fox body 5.0s, several newer Cobras (but not the newest), and my buddy's twin turbo 351.
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Old 04-05-2007, 01:08 AM   #16
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then you know what pedal effort is
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Old 04-05-2007, 11:07 AM   #17
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it's fun driving the fox body back to back with an early 80s accord.
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Old 04-05-2007, 11:13 AM   #18
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I hate going to a lighter clutched vehicle i always feels like i'm gonna push the clutch pedal through the floor or blow out my knee.
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Old 04-14-2007, 10:39 PM   #19
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400 stop n go miles on the clutch now, so it was time to install the Forge MBC. As indicated by my mechanical gauge, I'm at 8 psi dropping to 6-7 psi.

Car accelerates harder on the top end than it used to. I was loosing a lot of power with the stock clutch.
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Old 04-14-2007, 11:53 PM   #20
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Whoo-hoo! Now when are you going stand-alone?
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