Mustang and Ford Performance Forums banner
1 - 20 of 25 Posts

·
Registered
Joined
·
708 Posts
Discussion Starter · #1 ·
New McLeod RST install - carefully went through 550+ mile break-in period then went to the track last night. First run, didn't heat the tires good enough but made 7.81 @ 94.5MPH (1/8th mile track) with a 2.01 60'. Could smell the clutch a bit when I parked the car. Waited 45 mins and ran again....

I guess I slipped the clutch too much off the line and it got waaaaaay hot - went through 1st in a blur then the clutch lost all friction in 2nd and all I remember seeing was the tach heading to 6800 or so and let off. I coasted down the track and was able to drive back to my parking spot normally. Friends told me all they saw was a cloud of clutch smoke coming from underneath the car after I launched. The clutch got real hot I guess :-]

I drove the car home about 40 miles and it really drove fine. The clutch definitely has chatter in it now when taking off. I assume that's from what must be many hot spots on it.

I did a short test drive today and other than the extra chatter, it seems fine. I even nailed it in 1st real quick and it smoked my street tires as usual.

Question is: is this clutch ruined? Is there a chance it'll survive? Should I go ahead and bite the bullet and pull it out for inspection?

I did the install myself - is it possible that I got the clutch discs backward? I don't think I did but wonder if that's why it smoked so easy? Maybe it's not possible to install them backward? I have the side stamped "flywheel" toward the flywheel on each disc - I think.

It's a McLeod RST with a Fidanza aluminum flywheel. Got like 700 miles on it now.
 

·
Registered
Joined
·
18 Posts
That is my exact set up I'm about install into my car. I hope you figure out if anything is wrong. Could it be that the flywheel disk ( the metal disk insert in the alum flywheel) is burnt up? You can replace that disk for @ $60 parts. Good luck.
Jamie
 

·
Registered
Joined
·
293 Posts
this is the only part i can speak to Evangelist.

if you mounted the "bottom" disk first then the
ring/floater, then the "top" disk (both with flywheel
side toward the flywheel), then all that is correct.

mine has about 400 miles so far, i hope it holds up
when i finally get to nail it.

is it possible that I got the clutch discs backward?

I have the side stamped "flywheel" toward the flywheel on each disc - I think.
 

·
Registered
Joined
·
668 Posts
If you want to check for clutch slip, accelerate normally through first and into second, then skip directly to fifth (shift smoothly) and get on the gas hard. If the RPM slides upward without corresponding road speed increase, your clutch is slipping... If the engine just bogs, and slowwwwwly climbs up the revs, it's fine.
 

·
Registered
Joined
·
708 Posts
Discussion Starter · #5 ·
this is the only part i can speak to Evangelist.

if you mounted the "bottom" disk first then the
ring/floater, then the "top" disk (both with flywheel
side toward the flywheel), then all that is correct.

mine has about 400 miles so far, i hope it holds up
when i finally get to nail it.
I'm pretty certain that's how I installed it - that's how I intended to install it anyway. 8-] I tried not to disturb it from the way it came packaged. I would guess that I just slipped the clutch too much but don't know for sure. I'm going to give it a longer test drive tomorrow and see how it feels. Will pull and replace if I have to.

Thanks.
 

·
Registered
Joined
·
293 Posts
well hopefully it will start to quiet down some, let
me know what you end up doing

I'm going to give it a longer test drive tomorrow and see
how it feels. Will pull and replace if I have to.
 

·
Registered
Joined
·
708 Posts
Discussion Starter · #7 · (Edited)
Burned Clutch Pictures

I drove the car a couple of days and there was no sign of clutch slippage but it certainly smelled like burned clutch so I decided to pull the transmission and clutch to take a look.

It appears that the discs that contact the floater plate took the worst of it. I did have everything installed correctly btw :) Was sure glad to see that. There were no loose bolts or anything like that.

The clutch discs have a definite burned smell to them and the pressure plate, floater ring, and flywheel have definite hot spots on them. I've put pics up on Google at

http://picasaweb.google.com/levi.taylor/20090304BurnedMcLeodClutch?feat=directlink

Any clutch experts make out damage in these pics? The clutch and flywheel have about 640 miles on them. This isn't my daily driver so I'm keeping it down till I figure out what went wrong - part failure, installation error, or just plain driver error. If I have to get a new clutch then I will - just don't want to repeat the episode.

Is it possible that my TOB is jacked up? Maybe I wasn't getting full engagement? It was fine on the street but once I hit the track with the drag radials I had problems. I did a good 550 mile break-in on the clutch.

Thanks.
 

·
Registered
Joined
·
1,180 Posts
ok a few things

1 don't do clutch slipp launches with multi disc clutches the huge surface area vs a single disc causes much much faster heat build up and the thin floaters are very suceptable to heat issues.

2 just asking but at any time previously did you have anotther clutch installed that required a t bearing shim.. wich if not removed would cause this clutch to never fully be released.

3 the damage is clearly sever heat from slippage .. when you say broke in for 550 miles do you mean stop and go city driving ? alot of people stick one in and go on long road trip and think oh its broken it... but its the slipping then locking up of stop and go driving that seats a clutch.

also did you install a new fly wheel or have yours surfaced >? a poor surfacing can cause issues as well even with the best clutches.

twin disc clutches are fussy things the floater much be set up just right with correct clearances etc. so they can be hit and miss.

also are you SURE your t bearing was 100 percent a slightly week bearing that deosznt release the clutch fully ESPECIALY in a twin disc can cause drag during clutch input wich causes fast heat build up and premature clutch failure with seemingly no warning.

when it comes to s-197 mustangs I simply recomend puting a NEW t-bearing in any time the clutch is out .. yes i know its a extra 108 but the possibility for failure is just so high that i dont feel its worth the risk.

for a serious s-197 i always recomend the owner upgrade to a mcloud type t bearing as its just so much more reliable.
 

·
Registered
Joined
·
708 Posts
Discussion Starter · #9 · (Edited)
Heh, lesson learned on slipping the clutch I think. To answer the other questions:

It had the original clutch in it - approx. 9000 miles on it. 9700 miles on car now.

I broke it in in stop and go driving to and from work and a new Fidanza aluminum flywheel was installed with the McLeod clutch.

I did not change the TOB - I think I will put a new one in when the new clutch goes back in. I'm thinking of trying the Spec 3+. Nothing against the McLeod but I might try to change my luck with something else. I will replace the Fidanza inserts, too while I'm at it on the flywheel.

Thanks.

ok a few things

1 don't do clutch slipp launches with multi disc clutches the huge surface area vs a single disc causes much much faster heat build up and the thin floaters are very suceptable to heat issues.

2 just asking but at any time previously did you have anotther clutch installed that required a t bearing shim.. wich if not removed would cause this clutch to never fully be released.

3 the damage is clearly sever heat from slippage .. when you say broke in for 550 miles do you mean stop and go city driving ? alot of people stick one in and go on long road trip and think oh its broken it... but its the slipping then locking up of stop and go driving that seats a clutch.

also did you install a new fly wheel or have yours surfaced >? a poor surfacing can cause issues as well even with the best clutches.

twin disc clutches are fussy things the floater much be set up just right with correct clearances etc. so they can be hit and miss.

also are you SURE your t bearing was 100 percent a slightly week bearing that deosznt release the clutch fully ESPECIALY in a twin disc can cause drag during clutch input wich causes fast heat build up and premature clutch failure with seemingly no warning.

when it comes to s-197 mustangs I simply recomend puting a NEW t-bearing in any time the clutch is out .. yes i know its a extra 108 but the possibility for failure is just so high that i dont feel its worth the risk.

for a serious s-197 i always recomend the owner upgrade to a mcloud type t bearing as its just so much more reliable.
 

·
Registered
Joined
·
175 Posts
I slip my spec supertwin disc clutch for launches all the time. have well over a hundred launches on it without a hint of clutch smoke, smell, slippage or a problem.
apples and oranges... your clutch will handle 1400+ torque his RST will handle just over half that.
 

·
Registered
Joined
·
1,180 Posts
no its not false
period a twin disc clutch heats up exponentialy faster during slip its simple physics ..when a clutch is slipping heat is generated the amount of heat depends on two factors .. the material of the clutch and the overall surface area that is slipping..

your SPEC CLUTCH can hand twice what you are putting to it so it could have very much heat blueing and still hold the power your puting to it.
 

·
Im Not Banned...yet
Joined
·
5,362 Posts
no its not false
period a twin disc clutch heats up exponentialy faster during slip its simple physics ..when a clutch is slipping heat is generated the amount of heat depends on two factors .. the material of the clutch and the overall surface area that is slipping..

your SPEC CLUTCH can hand twice what you are putting to it so it could have very much heat blueing and still hold the power your puting to it.
no one said they dont generate heat you said dont slip multi disc clutches. That is false. you can slip them fine provided they can handle your power and the heat.
 

·
Registered
Joined
·
708 Posts
Discussion Starter · #15 ·
I know some of the Spec clutches have been pretty dismal but can I assume the Spec 3+, a new stock TOB, and a new friction ring on my Fidanza flywheel will be a good setup for my car?

Anyone know if I'll need to shim the Spec 3+ or is it a drop-in replacement?

Thanks for the ideas.
 

·
Im Not Banned...yet
Joined
·
5,362 Posts
for sure it will. i had the spec 3+ with the stock TOB on my car for over 500 quarter mile passes with no issue. The clutch had so much material left it is now on Thump_RRR's car and doing great. I switched clutches because i switched to a TR6060 transmission
 

·
05 BOSS 302
Joined
·
3,947 Posts
I needed no shims and LOVE my 3+
 
1 - 20 of 25 Posts
Top