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minuteman048
01-16-2020, 11:38 AM
Started researching this and I will be going with a Stage 1 Exedy upgraded clutch. What I am trying to decide on is should I go with a lighter flywheel say about 12 lbs.? Still looking for long term reliability with the possibility of a FI down the road. On my car this would help a little better with rev matching and still have a clcose to normal feel. Clutch pedal would be about 20% stiffer but I could handle that. This is what I am looking at and don't comment on the price. Im still shopping.

https://www.good-win-racing.com/Mazda-Performance-Part/61-1031COMBO.html

They mixed and matched the components and tested it so my risk is lower:

DESCRIPTIONOur street friendly 12 pound Exedy Flywheel combined with our Exedy Stage One Clutch kit...complete for an amazing price! Exedy is the premier Japanese OEM clutch supplier and EXEDY made your factory Miata clutch so when they told us they had finished a new organic disc heavy duty Miata clutch kit we took notice by installing one in our own Miata...and we love it.Increased clamping will take the abuse of autocross and track days and low boost applications. Will not hold near as much power as our ACT HD, but this EXEDY clutch gives a more stock-like release curve....very much like the factory clutch release curve! Pedal stiffer by about 20 percent. Kit comes complete with everything you need for installation including Pressure Plate, Clutch Disc, Throw Out Bearing, Pilot Bearing and Clutch Alignment Tool.
EXEDY Racing Flywheels are made from solid one piece billet Chromoly steel forgings. They are specifically designed to reduce weight and inertia for better engine response. Most incorporate special design features to enhance air flow to improve the cooling of the clutch. The ring gear teeth are milled onto the flywheel unlike an aluminum flywheel where the ring gear is pressed onto the flywheel and have the possibility of separating from the flywheel.

pdexta
01-16-2020, 01:36 PM
If someone in the group has a lightweight flywheel you can try I'd definitely want to give it a shot before buying. Light flywheels are one of those weird things that people either love or loathe.

I initially went with an ACT Streetlite (13lbs?) after reading reviews of people crying about lighter flywheels. Once I installed it I couldn't even tell the difference from stock. I eventually went to a Fidanza 9lb flywheel and I really liked it. Maybe I'm just oblivious, but I never felt like I had any driveability issues others complain about with a light flywheel. It's actually one of the few miata parts I've held onto, I know eventually I'll get another miata and that will be one of the first things I do to it.

Moral of the story, it's very much a personal preference thing so try to test one out first to see how you like it.

Agent☣Orange
01-16-2020, 03:14 PM
I too had a super light flywheel...Centerfor ce I think. I never had any drivability issues and neither did my dad who also went with the same flywheel.

minuteman048
01-16-2020, 04:34 PM
A guy at work had a souped up Mitsubishi with an ultra light flywheel. The driveabilility of it was horrible and it kept stalling out. He let me drive it and I did not like it. That was my only experience, but if you guys say it was ok, I will go with it. The one I'm interested in is the 12 lb flywheel.

Agent☣Orange
01-16-2020, 05:11 PM
Twelve pounds, no problem. You wouldn’t notice anything different going to 9lbs. If your friend with the Mitsubishi kept stalling out, he just hadn’t learned to adapt. Come to think of it, I had 9lb flywheel in my Mitsubishi Starion eons ago. It took a couple days to get used to but that big, 2.6L four-banger sure spun up faster after losing 20lbs of rotating mass.

Jaysz28
01-17-2020, 06:59 AM
I have never driven a miata with a lightweight flywheel. Stock is 18 or 19 lbs if I remember correctly.

I have a 12 lb clutch and flywheel sitting on the floor to put in the turbo car whenever that one gives up the ghost.

Joe Morreale
01-17-2020, 09:15 AM
After it was cut, just to clean it up, my stock flywheel was 17 lbs. You won't have any noise or drivability issues with a 12 lb flywheel. The clutch kit looks good but It states that it's good for low boost applications. What does that actually mean? Even 8 lbs of supercharger boost will give you somewhere around 180 whp, and the FFS is about 200. My Flyin Miata clutch is rated for just over 300 hp and it feels like stock. I wonder what the hp rating is for the Exedy one. Mine has about 30-35k on it. When I looked at it there was a couple hot spots where I slipped the clutch too much. Other than that there's a bunch of clutch left.

Do you plan on draining the trans and filling with new fluid. If so, have you made a choice what you're going to use? I've been happy with Amsoil, Redline and most recently Ford unicorn tears. But six speeds are finicky what you put in them. You could probably use and GL-4 synthetic and be good. Just don't get GL-4, GL-5 compatible fluid The GL-5 formula is known to soften syncros and shorten the life of the trans. If I can find it I'll bring a driveshaft sleeve you can put in the trans, so you don't take a bath, although from pictures I've seen you seem to enjoy that.

I also have not had issues of slave and master failures that seem to plague some people who install heavy clutches. You can drive it Saturday, if you haven't ordered it yet. I'll try to get it adjusted right. I have the 2 nuts jammed onto each other and it doesn't hold adjustment because I'm too lazy to lock it down.

kung fu jesus
01-17-2020, 12:37 PM
Just my $.02 of anecdotal experience:

12-14# flywheels are fine for the street. Less than that can be tiresome in traffic and stop & go traffic.

I highly recommend chromoly over aluminum for safety and reduced gear lash noise. A lightened flywheel at the 12-14# range will emit some lash noise versus stock, but not like an 8-10# aluminum unit.

ACT and Exedy flywheels are quality products. I don't know that a stage 1 Exedy clutch will give you enough headroom for adding F/I. I know the ACT HD clutch will, but stay away from the XT (extreme) clutches, unless you like doing leg squats while getting groceries. Whichever clutch you choose, stay with a sprung, full-face (not pucks), organic discs for OE-like engagement.

minuteman048
01-17-2020, 03:47 PM
That's what I read and am going for high end street and if ever go with boost it will be on the lower scale.

The kit I want to go with is a chromoly one piece unit with machined ring gear as part of the flywheel:


EXEDY Racing Flywheels are made from solid one piece billet Chromoly steel forgings. They are specifically designed to reduce weight and inertia for better engine response. Most incorporate special design features to enhance air flow to improve the cooling of the clutch. The ring gear teeth are milled onto the flywheel unlike an aluminum flywheel where the ring gear is pressed onto the flywheel and have the possibility of separating from the flywheel.

3900

pdexta
01-17-2020, 04:38 PM
I know the ACT HD clutch will, but stay away from the XT (extreme) clutches, unless you like doing leg squats while getting groceries.

Lol, that's some good advise! I had a ACT Xtreme clutch in my car and it's an absolute beast. I bought it used like 12 years ago from a guy that installed it, broke it in, then removed it because it was so stiff. I then ran it in all 5 of my miatas, taught 3 people how to drive stick on it, put somewhere around 150k miles on it, and the thing never even hinted at slipping. My left leg is easily 3x the size of my right leg.

If your only requirement of a clutch is to not slip and hold tons of power, then I highly recommend it. If you're looking for anything else from a clutch, then it's probably not the clutch for you.

kung fu jesus
01-17-2020, 09:44 PM
I ran an XT00 and 8# fidanza on my ‘92. My last turbo tuned to 240 BHP. Neither that, the S/C nor two dozen HPDEs made it slip. Response was awesome, especially at the track in N/A form, but it was loud and a bear in LA stop & go. I pulled it at 80k miles later, it still had a ton of life on it. I replaced it with an F1 chromoly flywheel and an HD ACT, it was still responsive, a lot easier to live with and a lot less noise. The F1 flywheel was 12-14# and I had to clearance the centerbore to fit the OE center bearing to fit right.

I am considering sending a spare 5sp out to be B&B’d, case bolted locally. I will definitely be ringing up ACT for a clutch again. Just never had an issue with their quality nor their performance.

Even at low boost, not taking account for headroom can glaze and ruin a disc through inevitable boost creep.

minuteman048
01-17-2020, 10:18 PM
Do you plan on draining the trans and filling with new fluid. If so, have you made a choice what you're going to use? I've been happy with Amsoil, Redline and most recently Ford unicorn tears. But six speeds are finicky what you put in them. You could probably use and GL-4 synthetic and be good. Just don't get GL-4, GL-5 compatible fluid The GL-5 formula is known to soften syncros and shorten the life of the trans. If I can find it I'll bring a driveshaft sleeve you can put in the trans, so you don't take a bath, although from pictures I've seen you seem to enjoy that.

I also have not had issues of slave and master failures that seem to plague some people who install heavy clutches. You can drive it Saturday, if you haven't ordered it yet. I'll try to get it adjusted right. I have the 2 nuts jammed onto each other and it doesn't hold adjustment because I'm too lazy to lock it down.

I am going to drain the 5 speed trans before pulling it and reuse it. It's the Ford synthetic and been in there two years. The front and rear seals will be replaced along with the rear main seal on the engine. Already have those parts as well as the exhaust gaskets and a replacement downpipe. A fresh slave cylinder will also go in. I am not planning on getting an oil bath again. That was Jesters car and he set me up for that. Have not seen that picture in a while.

kung fu jesus
01-18-2020, 12:28 AM
That was the other thing, the heavier XT clutch, preventative maintenance was replacing the slave annually, the master every other year because it’s cheap. The longer, braided SS clutch slave lines that eliminate the hardline coil to the slave are a huge time saver to replacing slaves.

minuteman048
01-18-2020, 07:57 AM
That was the other thing, the heavier XT clutch, preventative maintenance was replacing the slave annually, the master every other year because itís cheap. The longer, braided SS clutch slave lines that eliminate the hardline coil to the slave are a huge time saver to replacing slaves.

Put the SS braided line in years ago. One of the best mods out there. Slave cylinder change out with a quality unit every other year especially before a road trip is a ritual. I believe in predictive maintenance on critical parts to keep you going like in the aircraft industry.

Joe Morreale
01-19-2020, 08:04 AM
I bought the 949 braided line many years ago. Now the nut, at the hose side, is frozen. I have to twist the whole thing to get it off the slave. If I replace it, I'd like to get a line from the master to the slave. Eliminate the hardline all together.

minuteman048
01-19-2020, 08:17 AM
I bought the 949 braided line many years ago. Now the nut, at the hose side, is frozen. I have to twist the whole thing to get it off the slave. If I replace it, I'd like to get a line from the master to the slave. Eliminate the hardline all together.

Are you using the right cube wrench? You can also get a replacement hard line.

Jaysz28
01-20-2020, 08:09 AM
I am going to drain the 5 speed trans before pulling it and reuse it.

You can pull the trans with it full if you plug the output shaft with a used driveshaft yoke. We do it at the shop and track a lot.

hell, we have 5 motor swaps to do before Feb 5th and we won't spill a drop of MTL doing it! lol

minuteman048
01-20-2020, 12:49 PM
You can pull the trans with it full if you plug the output shaft with a used driveshaft yoke. We do it at the shop and track a lot.

hell, we have 5 motor swaps to do before Feb 5th and we won't spill a drop of MTL doing it! lol

Joe dropped one off so yippie!

SmileyFace
01-22-2020, 11:08 PM
I agree with all the good information and advice that everyone gave you, now all you can do is purchase the clutch you want, meets your needs and performance requirements.

minuteman048
01-23-2020, 07:43 AM
I could probably look this up. I am assuming on this transmission you have to drain it to replace the seals?

kung fu jesus
01-23-2020, 09:44 AM
It's the easiest way. It's $40, just replace the fluid.

minuteman048
02-17-2020, 11:50 AM
In about a week I order my clutch kit and drive shaft. Just ordered my replacement bolts for the drive shaft. Already have the rear main seal, front and rear transmission seal and gasket, exhaust gaskets, and replacement used down pipe. Off for spring break and the fun begins.

SmileyFace
02-19-2020, 12:02 AM
I want to be there, so let me know as soon as you have the date and time, so I can be there.

Agent☣Orange
02-19-2020, 12:05 AM
Same here. I need the free food.