Clutch Time Part II
 

I made a clutch inquiry here a month or two ago. When the clutch was slipping a little. Now it's slipping a lot, so it's go time.

My requirements are:
Holds whatever a stock 1.6 and Tdo4 can produce
Low pedal effort
Good street manners
Capable of being driven by a woman in traffic
"Easy" installation.

The clutch will be swapped in a shop, so I'll have access to a lift, tranny jack, air tools, and all the acuturements expected in a modern automotive repair facility. What I don't have is time, nor do I have any experience in a clutch job. So I need something straight forward with little/no engineering.

So after M2's and Sam's experiences with their spec clutches, I'm leaning towards clutchnet as recommended by several including WOT. So, since I'm a clutch newb, what do I need? What "color level" from clutchnet would work? What gaskets/seals? Is this the time to do new motor mounts? Should I use a lightened 1.8 flywheel, or retain my 1.6 flywheel?

Someone on miata.net was selling the FM clutch/flywheel combo (I refuse to call it a happy meal) for $550. I'm not sure if that'll meet your requirements or not.

I think you'll have a tough time finding consensus as to brand. I have had zero problems with my spec, but after hearing of Sam's problem I'm a little leary when I start making bigger numbers.

Unless you are getting a good deal I wouldn't bother with a light flywheel. I just don't think that you get a big gain back on your investment like you would when you are N/A. If you do want go with steel instead of aluminium. My aluminium flywheel is noisey, but that's a 7-8lb unit.

I would use a 1.8 kit and flywheel over 1.6. NA I would say stick with the 1.6 flywheel, there are better options that are more streetable with the 1.8 flywheel.

If I were to do it over I would do the SPEC 1.8 Stage 2+, or just suck it up and go with the heavy ACT setup.

The ACT Extreme seems like a good kit, but I can't live with one because of the heavy pedal (bad knee). The HD doesn't look like it would hold up to my power as FM only recommends it for their voodoo cars, and recommend the extreme for FMII power. I would also like take off and modulation to be smooth so the car could be driven in rush hour by the wifey, if she had to do so. I'd really like something stock-like, but with the ability to hold 2.5X stock power.

I'm not thinking of a fancy light flywheel, but just machining down an oem 1.8 flywheel to approximate 1.6 flywheel weight. Which would give me increased surface area without much/any penalty.

I'm scared of Spec. And they don't seem to stand behind their product in the event of failure. I don't have time or patience to do a clutch swap twice.

I don't know if it actually does, but the MAX-5 clutch I have is rated at ~250 ft-lbs according to the records. I can attest to the fact that it feels much like the stock clutch, but maybe a little lower engagement. Frankly, you might never know that it was different than stock, except for its supposed holding power. Just a thought.

I don't think lightening the flywheel is worth the effort, but that's just my opinion.

Check out www.mvpmotorsports.com. They have all the popular clutches and descriptions. I bought my gear through them and was very happy with the service. They have a little blurb about each clutch that might help you out. With your requirments you are going to have a tough time finding something that works, but I'm sure there is something out there for you.

I wonder if you could get around the heavy pedal with a different master/slave arrangement?

Jay

I would have to agree with jay on this. Plus it adds just a little bit of load to the motor, which adds a little bit of momentum which makes street driving a little bit easier, just my opinion. I put a lighter flywheel in my camaro, and it made the clutch extremely picky, and is now more like an on/off switch. For the specs, if you really want the holding power, go with the stage 3, or if they have it for the miata, the 3+, that is where you are going to get the true power holding. I will be installing the act that I have in my room after I get back from visiting my parents in Colorado, so I can give you some feedback on that, but that won't be until mid next month. I have the one that is rated for 256lb-ft, whichever one that is.

Come on fellas. What items do I need to order besides the disk and pressure plate?

throw out bearing...pilot bearing right? The kits come with them...or whatever 2 bearing you need.

Unless you mean like parts...check this thread by Samnavy:
https://www.miataturbo.net/forums/sh...?t=5860&page=2

I just bought:
-ACT Clutch kit XT PP/ST disc
-Spark Plugs
-Rear main seal
-Front tranny seal
-Rear Tranny seal
-Upper shift boot
-Lower shift boot
-CAS O-ring
-Upper/Lower shifter bushings
-Brainiac's flywheel whenever he pulls it.

Except I'm probably going for a clutch kit recommended by clutchnet instead of the spec.
This everything? What bearings do I need? No bearings included by clutchnet.

Pilot and release bears. An alignment tool might be handy as well.

Got a very bad feeling from clutchnet and didnt want to go with Spec because of the trouble reported on this forum. Went with the 1.8 ACT HD package from FM. They say it will hold up to my longterm, longshot goal of 240rwtq.

Ouch it still hurts :ky:

Pretty much exactly the same experience here.

Hopefully yours has the later material that doesn't squeak. Mine squeaks. I 'm hoping we can find another clutch manufacturer beside ACT or Spec that has a good streetable, quiet, durable for 240HP clutch.

I've mentioned it a couple times, but somebody should check out the MAX-5 clutch. The later versions are very very nice.

What gave you the bad feeling from clutchnet? I had a informative conversation with the guy there that helped me decide which disk to get. Shipped the same day I placed the order.

Wish I had an informative employee, but it wasn't the case. Was communicating via email with Alex at clutchnet. I told him my desires, and he recommended a $195 pressure plate and $175 disk, but didn't give me either part #. I couldn't find any miata parts on their site that had corresponding prices. So I asked him what the part #s were and he emailed me back saying that I needed to pick out the parts I wanted out of their catalog. So I responded, explaining that I was ok with the price he quoted me, but had no idea how to proceed to order as he never gave me the part #s of the items he recommended. Alex never got back with me.

So I called FM, told them what I was after (holds power, low effort, easy to drive). Without hesitation, Mark recommended the ACT HD package. He said that it's been on Keith's car for 40k miles without a problem, and Keith's car makes 50-75 ft lbs more than my 1.6 ever will.

Might have cost me a little bit more to go with FM, but not more than $10 or $15 (clutchnet doesn't include bearings, FM does). But I got the service I needed with FM. Which is definitely worth a little extra.

It will hold and feel good. I called them asking about mine as well (1.6 HD). And surely enough they were right to say anything under 12psi with my turbo will hold...that's right where mine is letting go.

yeah, I don't blame you for going elsewhere.

Yeah I was thinking of going with the 1.8 because I've read that yours slips. Mark recommended the 1.8 off the bat. Keith's car makes 300 lb ft of torque (dont remember if that was flywheel or rear wheel) so there's no way it won't hold up on my car.

I acutally haven't gotten it to slip since that one day when NeoGenesis2004 was in the car. but still I want to eventually run 250rwhp so I might as well not risk it. plus i was already going to drop the tranny.

re ClutchNet... I think Alex and Oleg are the owners (russian accents?)

they've always been a little weird to deal with for me too but somehow got everything right more than once for a decent price. I think part numbers aren't something they're used to.

What is the best non-puck disk that clutchnet sells for the 1.6?

I still wish FM would have straightened out their kevlar clutch problems with Clutchmasters. Some failed because of a QC problem with the rivets. I had a good one though that held the abuse of an early FMII at 220 rwhp and had stock pedal effort. I might have to try clutchmasters again if this Spec stage II starts slipping.

Frank

I had to be persistent to get the info from clutchnet guys, but the product looks top notch and has worked well for the first 200 miles.

though this looks like a puck disc, it doesn't grab like one because of the friction material. I was told this is the highest level non-ceramitallic they have.

Well that's all the endorsment I need! :) If my SPEC setup goes south I'll give this disc a try, then I can live my life a 1/4 mile at a time.

Thanks for the recommendation.

frankly I think organic.

if you want drivable, get a heavy pressure plate and an organic disk. sure it'll hurt your leg but the rest will work right.

I have a Spec stage 2 with less than 5K on it installed in the car now. In the event that I have trouble I'd like to replace the disk only if that is indeed the potential weak part of the Spec clutch.

Who knows, I might be just fine with what I've got. I was just considering options in the event that things go south.

maybe that's what alex had in mind for me.

heh first 200 miles on the car, or first 200 after break in?

What is the break in period for an ACT?

I think it is usually 500 miles or so isn't it?

Every clutch i'm familiar with 500 miles is the safe zone for break in. In other words, one good weekend to Atlanta and back.

Yep 500 miles

That'll be a tough 500 miles. Might take me 2 months. :td:

What do I want to avoid--fast starts, power, or both? Can I bring boost down to greddy stock 5-6 psi (ugh) and take it easy, or should I totally keep it in vacuum?

Traffic is NOT a problem here.

I also beleive that those 500 miles are supposed to be in traffic :)

My dad explained to me that you don't want to shock the clutch. Try driving with an open cup of coffee on your dash.:bigtu:

the thing is you dont really change coefficient of friction when you use kevlar, carbon, fibery whosit, or organic. it's all pretty close. you only get it by going to a puck (sintered ceramic/metallic, copper, etc) but it also means no dynamic slip (smooth engagement).

that's the key to a good clutch. low dynamic coeff of friction + high static coeff of friction. there isn't such a beast.

maybe I should design a kevlar-copper alternating puck setup. that'd be real cool. have the kevlar engage first and then once it's there, let the copper grab.

what about something like I'm putting in?

The PP side is a standard 23-spline disc, the flywheel side; (8) pucks of kevlar material.

I'm thinking about these guys:
http://www.dxdracingclutches.com/home.html

They did the clutch in my vw which has a slightly stiffer pedal feel, and held 410lb/ft at the wheels. He quoted me a price cheaper than the website in email, and said he can raise the engagement point for us people that don't like pressing the pedal all the way to the floor.

I know results are not the same from each application, but atleast the friction material stayed on the disc unlike my clutchnet disc that only lasted 1 week.

Don't do things that stress the clutch...like put a bunch of torque on it. Stop and go traffic will break the clutch in fastest. After 500 city miles, drive the car progressively harder while not allowing slipping, until you give it all you've got.

i've seen those types... like the centerforce dual friction ones.

as far as kevlar goes, it's a hard material to deal with... it glazes easily and has a lower cf than organic. but it engages nicely in my experience.

I had this on my celica alltrac:
http://www.toyheadauto.com/J-pegs/TRDClutchKit.JPG

and it mostly made stink smell when i did clutch drops.

so if you could find a way to make ONLY the kevlar engage first, then you could have nice slippage and when you were, say 50% engaged, have the copper take over... bam power holding and decent engagement. question is: how do you make the kevlar not wear out right away.

I was thinking maybe using a marcel under the kevlar but not the copper... hrm.

Bag on it from the start and then post on the internet what a piece of shit it is :)

When I broke mine in I just avoided drag launches. I was only a little way into the break in procedure when I did a track day, but that's not too hard on the clutch I don't think. Seems to be holding fine.

Does the kevlar only start to glaze if you abuse it like dump hard on it? or will it heat up and slip between shifts?

yeah here is what my junx looks like:

Mine only glazed on drag launches at a prepped strip. It bounced back when it cooled down. I never had it slip on day to day spirited high boost driving.

Frank

sounds fine to me, even with the 7" rear I doubt I'll ever dump the clutch.

My spec disc was originally kevlar pads and they wore out in 5k miles. That organic puck disc looks like the thing hustler had grenade in his vw- it's got the friction pad ring riveted to a disc, which is then riveted to the hub center. Lots of rivets.