smoked my clutch, what should I get now?
 

I'm slipping my ACT clutch (HD pressure plate and full face organic disk, rated for 245ft/lb and 13lb flywheel)

I need something that will hold more power BUT I really dont want a super heavy pedal. I'm a chick so I'm not really strong and a heavy clutch pedal is difficult for me to drive with for more than a short time. I do street the car but I take it either drifting, auto-x'ing or OTD almost every weekend now so it gets beat on a LOT.. especially when drifting.

I'm making 250wtq and 280whp currently, but after I get a clutch I'm going to turn up the boost for 300wtq and 330-350whp give or take.

So my question is, is there any combo I can come up with that will hold around 330wtq to be safe, that wont be super heavy? And no, I can't afford a twin disc. I was thinking ACT sprung 6 puck with a flyin miata level 1 pressure plate? Idk if those would fit together/work etc.

Any advice would help! (yes i have googled and searched threads here but a heavy pedal doesnt seem to be a big problem to you guys like it is for me!)

FM2 or 949.

FM2

I called flyin miata a few weeks ago and talked to them about the level one and two, they said the FM2 has a very strong/hard to push pressure plate and he recommended the lv1 to me but I don't think that's going to hold up.

Centerforce twin disk...no balls.

You are not going to find a clutch with a light pedal feel that will hold that much torque.

guyyyysssss FM2 is too heavy and I cant afford a twin disc. gotta get creative here :confused:

​​​​​​​Look at my post right above yours. It has the answer. Either turn down boost, or live with the heavy pedal.

aw man :(

drive a mustang, then call the FM2 heavy...

actually, drive a miata with the ACT XD, then call the FM2 heavy...

I had one of those dual friction ones in my miata... it didn't hold well.

There's not much creativity to be had, only physics. Your clutch rating is based on coefficient, clamp load, effective radius, and number of friction surfaces. Aggressive coefficient means bad for the street and also expensive. Effective radius can't be changed due to bell housing constraints. Clamp load makes the pedal heavier. Number of friction surfaces is the ticket, aka 949 twin disk.

I'm actually curious just how heavy the FM2 is. The FM1 made my clutch pedal softer than stock. Maybe see if you can drive someone's turbo car in the area to see if the clutch pedal is livable? I feel like Dillon (Erat) has an FM2, but I'm not totally sure.

https://cimg9.ibsrv.net/gimg/www.mia...e71f3d41ad.jpg

:sadwavey:

this makes sense, thanks for learnin me. I see you're from farmington hills MI, I'm in Rochester! (I work in warren so thats a little closer)... do you have a FM2? ;) ;)

I can guarantee you won't want to try my clutch. :giggle:

https://cimg6.ibsrv.net/gimg/www.mia...2ac94db2aa.jpg

I don't have a way to measure how stiff mine is, but I can say that the FM2 is far stiffer then the FM1. I honestly have to say it is stiffer then the clutch in my 7.3L power stroke.

yikes!!!! does anyone know around how much poundage it takes to depress a FM2? 949 says OEM is around 20lbs to push, and their super miata sport clutch is around 35 lbs to push. I can't find any rating on the FM2 but that would be a big deciding factor.

Some data from Keith (at FM) here.
FM1 18lbf
stock 96 22lbf
stock msm 25lbf
FM2 26lbf

Data is old but seems close to consistent with

I daily my NA with the FM2 clutch. It's not bad at all, will feel like stock after two or three days. Only time I notice how heavy it is, is when I jump in my stock clutch 95 and smash the clutch to the floor the first few times lol.

I blew the springs out of my FM2 friction disc with just hard street driving... I wouldn't use it on a drift car. I Currently have an FM2 Pressure plate with a 6 puck competition clutch friction disc that seems to be holding up well. As others have stated the pedal on the FM2 is far harder than stock but still manageable in my opinion. Also for what its worth, Competition Clutches makes the flying miata clutches. You may be able to go with the FM1 Pressure plate and use one of the various friction discs they offer to get it to hold the power you want.
-Mike

You forgot: add squats and calf raises as part of your routine. Then no clutch will be too heavy. Bonus, your legs will get firmer and more toned!

I never thought the FM2 was that heavy. the FM1 felt like stock if not softer.

FM2 is buttah

http://www.kitchengadgetvegan.com/up...3606_orig.jpg?

This is what I was hoping!! thanks! :) I have also heard of a few others whose FM disk shattered. Idk the back story though.

Was there a defective batch of FM2's or something? I remember reading something about spring issues a while ago.

They had to be paired up in cars with ST valve guides.... Otherwise, good to go. :giggle::giggle:

:noes:

My mom (at the time 54 years old and 4'11", maybe 120lbs) was able to handle FMII. That should be a good point of reference.

Drivability on an FM2 far outweighed the chatter of a stage 4 pucked competition clutch or the tiny amount of added pedal effort.

It'll also holds enough torque for many.

I called up 949 yesterday and talked to them about their super miata clutch (with ceramic 4 puck which they're currently out of stock on) :( :( :( :(

but he told me one of the goals in making their pp was for it to be easier to push than the FM2, roughly 25-30% easier. it's claimed to hold 340ft/lb which would be perfect for me.
does anyone have this clutch? how does it feel?

They won't have them in stock for roughly a month and I've got a big track event early June. ugh.

Not sure why you're skipping leg day when you have options available now. IMO, with a lighter pedal engagement and high tq capacity of a 4 puck, I think you're going to be forced to be skilled on the pedal to avoid chatter and roughness as noted above. How rough do you plan to be on the clutch for the track event? Are you just looking for durability?

It's a two day track day event GRIDLIFE BRO! (I'm just doing HPDE not time attack or drifting or anything) but the last drift event I was at it would slip bad (smoke coming in the cabin bad) any time I tried to use 4th. Seem's to be fine 2nd and 3rd. It's a fast track so I will definitely be needing 4th and possibly 5th, but I won't be dumping the clutch to get it sideways like last time :p

terms of durability I just need a clutch that will hold the power level I want which is ~330-350 whp and probably low 300tq. I would prefer harsh engagement over a heavy pedal

I daily an fm2 and I don't think it's heavy at all. I have an MSM so according to the numbers posted earlier it is barely heavier than what my stock clutch was. I actually find it very easy to modulate because it has some resistance in the pedal instead of being floppy like some lower powered stock clutches can be. However, I am a man and I don't skip leg day so YMMV.

EDIT: I should say I HAVE DD'ed this clutch. The miata is no longer my DD but it was for 60k miles, much of which was with the fm2 clutch.

This ^^ :likecat:

Yeah, my FM2 clutch isn't bad at all. Heavier than stock but not as bad as my Mustang clutch was. Far better drivability than any puck clutch I've driven - OE level progressivity I'd say. I'd rather a heavy clutch you can release smoothly than a lighter clutch you have to ride in order get a smooth takeoff.

i currently have a Competition Clutch stage 4 in my NA. It sucks in traffic. I keep telling myself I need to man up, plus it keeps people from asking whether they can drive my car. But at night, when I quietly cry myself to sleep, I wonder if I could pair a stage 3 solid disc with my stage 4 pressure plate and still handle 300 whp?

Don't waste your money on FM products. Spec, Competition... all equally low quality.

949 did the legwork to obtain much higher quality parts for their clutches.

Wait for the 949 sprung 4 puck. I'm driving on stock power levels with it, zero chatter. Normal clutch pedal pressure, narrower engagement, and slightly grabby, but how a clutch should be. A little noisier than stock on decel, on top of just a lightened flywheel.

What's your basis for the 'FM products are a waste' line?

Also, don't you think it's a bit strange that you're giving advice on a clutch that you're using at stock power levels? Have you ever driven one of them at anything resembling the OP's power output? i.e. what's your basis for the recommendation outside of a complete trust in Emilio? Not that there's anything wrong with that...

Well, I should have said, don't waste your money on parts that FM resells. They purposely use low cost parts. I have had nothing but early parts failures from them. clutch slaves (two of them rusted out and leaked in under 6 months) throw out bearings/release bearings (one early failure and the replacement was defective) pressure plate (defective and was causing clutch slip with stock power levels)

I just tell people to steer clear of their low cost high volume high profit parts. Just my opinion and experience with them.

I've gone though 3 clutches in 3 years, and I'm finally happy with the sprung pucked 949 clutch. They have a lower profit margin, much higher quality components.

Sure I only have stock power levels, but I'm just giving my input on clutches. I don't want other people to deal with the crap I've dealt with, just trying to look out for members if I can help them. If I'm wrong, fine, but I'm still steering people towards the higher quality clutch.

I wasn't doubting you. I was just curious as to your rational after all these folks were recommending the FM2!

I feel like you're definitely an outlier. Their clutches are always the first to be recommended and they don't have a reputation for faulty parts. Most users have been more than satisfied with their clutches. I had to replace the clutch disc on mine after 50k mile due to a leaky rear main seal and the disc still had plenty of thickness to it. It sounds more like you just got incredibly unlucky.

Competition clutch manufactures the twin disk. Which seems to be pretty good...

Fwiw I recently upgraded to 949 twin disc carbon/Kevlar and find it to have really good manners once adjusted properly for shorter travel. As light or lighter than oem clutch in my 05 wrangler. The faster revs are awesome too if you don't mind a little buzz on decel.

I went with FM2 on my last rebuild and found it to be both strong and comfortable. Basically stock feel but way stronger. I don't mean it's exactly like a stock clutch (which was incredibly soft) just much closer to stock feel than my old six puck setup.

Only really notable things about it compared to stock are:

• Long pedal travel. Really long. You will have to adjust stuff.
• Slightly stiff but nothing terrible. I'm guessing this is paid for via long pedal travel
• Easy to engage/modulate

For the strength you get it's pretty easy to live with. I file the complaints about the FM2 with the complaints about poly motor mounts. It's the sort of shit people complain about the first day and then they get used to it and stop caring.

Competition Clutch also manufactures the FM clutch.

When my clutch slipped on the dyno I had it sent in and CC said nothing was wrong, car just overpowered it. Sent me a new one anyway and FM sold me a brand new one for half off. Sold those and bought the 949 Twin disk.

FM was easier to drive, I just wish it held up. Twin disk isn't so bad, but it's a sharper engagement way up high as adjusted per instructions.

​​​

Correct flywheel machining is paramount for clutch life, especially in a Miata.
The relationship between the flywheel surface AND the "steps" is often overlooked.

https://cimg1.ibsrv.net/gimg/www.mia...ce91887452.jpg


The "depth", meaning, how far the bosses stick out from the flywheel surface should be no more than 19 mm, and 18.65 mm is the ideal depth.
I have seen flywheels with over 20 mm depth, and one at 22 mm.
This significantly reduces clamping force and friction material life.

I stay right at 18.65 - 18.70 mm, and have not had a clutch problem ever since I found out about this little tidbit.

All you need is a straightedge and calipers, and you can measure your flywheel before installation to save a ton of headache later.