Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   General Miata Chat (https://www.miataturbo.net/general-miata-chat-9/)
-   -   Help determine which component is wrong with clutch and ruined my track days (https://www.miataturbo.net/general-miata-chat-9/help-determine-component-wrong-clutch-ruined-my-track-days-52742/)

miatauser884 10-18-2010 02:33 PM

Help determine which component is wrong with clutch and ruined my track days
 
I had a track weekend at Barber, and my clutch started slipping. This is an almost new ACT extreme pressure plate with organic disc. It is rated for well over the 250tq I produce at 20psi. The slippage started slowly, and became worse and worse as the laps increased. I then reduced the boost, and this helped for a little while. Possible problems:

Bad pressure plate?

Organic disc 282 ft lbs?

I did not resurface lite-weight flywheel and pressure plate?

Possible rear main seal leak and oil getting on clutch?

What would you expect to be the problem. Should I just buy new clutch and pressure plate to be safe? I will definitely resurface the flywheel. Just resurface flywheel and current pressure plate? I will go to a six puck regardless.

y8s 10-18-2010 03:44 PM

250 torque you produce at the wheels? or at the flywheel?

shlammed 10-18-2010 04:58 PM

disc'd clutches hate heat.

miatauser884 10-18-2010 05:47 PM


Originally Posted by y8s (Post 645022)
250 torque you produce at the wheels? or at the flywheel?

Crap, you made me realize I have been thinking in terms of rear wheel torque and not flywheel torque.

What's the avg tq loss people are using when determineing the clutch they need.

Would you go organic disc or sprung/unsprung puck?

miatauser884 10-18-2010 06:04 PM

Now it looks as if I was exceeding the limits of the performance street disc. If I assume 12% increase in torque at flywheel, then I would be at 285 lb lbs. This probably led to glazing the pressure plate and the flywheel.

Thoughts on this solution.....

ACT 6 puck clutch, resurface flywheel and pressure plate (or at least scuff the pressure plate.

Since it is an extreme pressure plate it should be good for 390 ft lbs, excessive, but I'm sure I will eventually push to ~ 300 ft lbs at rear wheels.

fooger03 10-18-2010 06:08 PM

glazed surface of new unbedded clutch

unless there's oil coming out of the weep hole at the bottom of the transmission

edit: crap, beat me to it

matthewdesigns 11-27-2011 03:07 PM

djp0623, reanimating this one to find out what you discovered. I'm ordering a clutch in the next couple of weeks and would like to hear about the outcome of your issues since it's been a year or so.

My car is not a dedicated track car, nor is it my DD, but the clutch needs to be able to withstand the occasional track day and frequent mountain road attack. I figure the FM1 setup would be perfect for a street-only car, and I don't have any intention of surpassing it's power rating. But I know puck discs are much better with heat/abuse. I've driven an unsprung puck disc in the past (daily for a while) so I know how those feel, not worried about engagement, etc (I would go sprung this time, however).

miatauser884 11-27-2011 03:28 PM

My issue turned out to be a warped pressure plate. IT was only contacting efficiently on about 33% of the disc. I ended up going with a sprung 6 puck. You get used to driving it on the street, but it doesn't leave you the opportunity for lazy days. I typically rev high on take off for a smooth exit from traffic lights. I would put an extreme disc in it next time. The puck clutch is great for when I want to drive like a bat out of hell.

matthewdesigns 11-27-2011 04:21 PM

Ah, so not necessarily a disc issue. I'm still leaning towards the FM1 based on its reviews and the relative civility of a full faced disc. Thanks for the update and info.

TorqueZombie 11-27-2011 11:03 PM

I've got the FM happymeal stage 1 in my non-boosted '97 and like it a lot. The peddle effort increase from the fried stock that was in it is so little I thought I F-ed it up. I bled the line for a week thinking it had air cause it was softer than I expected it to be for a "performance clutch". This coming from a Spec 6 puck sprung hub in a boosted S14. I needed lead shoes for that thing and the engagement zone was tiny.

matthewdesigns 11-27-2011 11:33 PM

That's how the solid 4 puck/2600# ACT setup I had in my Talon drove. I want to avoid that this time so the FM setup is looking good to me.

pug106 11-28-2011 04:04 PM

Is the flywheel aluminum or steel ? I had a lot of issues with aluminum flywheel on my b18c swap crx. Because aluminum warps with heat on the third lunch.


All times are GMT -4. The time now is 07:28 PM.


© 2024 MH Sub I, LLC dba Internet Brands