Another clutch test fail?

[1fastpony]

Installed the Spec 2 a couple of months ago. Everything seemed good to go so I wanted to see if it could not only handle normal N/A track visits, or the occasional 75rhwp n20 hit. This clucth is rated at 599 tq and, spent some phone time with reputable speed shops. Consensus was it should work fine. Also installed the braided line to HTOB and drained the old tranny fluid and added Mercon IV. Car shifts smoothly during normal driving and speed shifting as well. CAR Tranny/Clutch engages and dis-engages well under WOT, no Notchy feeling, peedle is very light during WOT speed shifting. Been to the track twice and no miss shifts, all confidence is returned. Well it's been hot down here and there was a Event going on at Gulfport last night so me and my youngest deiced to go see and make a n20 pass. We didn't find out till we got there that you could take a passenger along for the ride. So my 12 yr old got to experience his first track run and it was a solid 12 second run N/A with crappy traction...1.8 60'.

He was all smiles.

Next up was the n20 run. Car cooled down good 45 minutes under the EH2O pump. Bottle on. good psi..1050 psi. Burn out good, stage and ready to go. Car next to me is a mid 90's Munstang Gt with some bolt-ons and cam...low 14 second car. Light turns last amber and we leave about 4500-5000 rpm. Window switch is set at 3200rpm to 6100rpm and spraying out of the hole. Car initial hooks and you feel that n20 TQ hit and it gets soft. shift to second and and same but you could and see/hear the car/tach over rev back in forth. By the time I went to third it was worse so half way through the gear I shut it down and let the other car go by. Son ask why you slow down and I told him the clutch gave up.

Go to the slip shack and left and could tell the clutch seemd soft starting off and into second. Back at the pits opened the hood and there was that smell. Not bad but there. James (JRC07GT) came over and mentioned it looked like I left like Garmma leaving the grocery store...HA HA.

Well, that was it for the night. Aired upt the M'T Dr's and let the clutch cool a bit and drove home 45 hwy miles. After cool down it seemd back to normal when letting the clucth out from a stop light and no slippage during some acceleration. Did the 4th gear low rpm and 5th gear test and appears no problem there.

Not sure what went wrong. It was a hot night so I don't know if that was a factor in the clutch cool down between runs. Thought I would again post this info for others to consider.

 

[JeremyH]

S197's and specs just dont get along, i have heard too many horror stories about specs on many different applications. Hopefully the slave is intact and you can get some usage out of it.

 

[onebadgsx]

go with the exedy. they make the rousch clutch, and many other factory and performance clutches. i love mine.

 

[1fastpony]

Well I'm going to give it one more try on the n2o and see if it lives. Have heard good and bad depending on stage type. The clutches initial grab/clamp is strong and sudden. I'm wondering if something I did but can't isolate. The last clutch, CF DFC would firm up when raising the rpms before launch but didin't have the steel line. This one gets softer/lighter foot peddle and shifts really smooth at high rpm and when you release grabs hard. One thing I have thought off is, the release point of the clutch is at the top of the peddle so riding the cltch or having your foot just barely resting on the peddle might make a difference. I have had clutches is the past where you can do this since due to release ponit was around the middle of the clutch.

Have you guys ever had a clutch peddle with this light pressure during high rpm WOT?
Or, could this be due to the steel braided line keeping the HTOB pressure up for good engagement and dis engagement?

The jury is still out but almost unaminous on the decision.

 

[JeremyH]

Its the stiffer pressure plate in the higer spec stages that give the oem slave trouble and caus problems. Thats why the twin disc rst works so well it has lighter than stock pedal and pressure is just like stock.

 

[dysan]

The low pedal requirement on my spec 3+ gives it the as light if not lighter pedal pressure as well. The failures I've seen with the specs has been with people who did not get that option.

I still believe mine will be fine.

 

[1fastpony]

Its the stiffer pressure plate in the higer spec stages that give the oem slave trouble and caus problems. Thats why the twin disc rst works so well it has lighter than stock pedal and pressure is just like stock.

That's correct from what I have heard. However, I have a Spec II. Those problems you speak of have been with Dis engagement of the disc during shifts which causes binding up or notchiness of the shifter. I don't have that symptom, it shifts great. When you let the clutch out the disc is suppose to clamp back against the flyhweel and that is where the incident of slippage occured.

Today everything is great. drove the car with the Dr's on. took off from a stop sign in a slighty remote area and just hamard it from 1st through 3rd and it just laid two black thick tire marks all the way up into 3rd. 3rd gear mark was probably a good 10' or so.

Please expond on your response. Also, I see you post your dyno numbers but do you have any track seat time? You know it is very different street to strip.

The low pedal requirement on my spec 3+ gives it the as light if not lighter pedal pressure as well. The failures I've seen with the specs has been with people who did not get that option.

I still believe mine will be fine.

Yep, mine is light for sure. WILL SNAP YOUR NECK BACK during speed shift or just normal spirited driving.

 

[Rypper1]

The low pedal requirement on my spec 3+ gives it the as light if not lighter pedal pressure as well. The failures I've seen with the specs has been with people who did not get that option.

I still believe mine will be fine.

Most of the Spec failures I have seen have been 2/2+. I had the 2+ and it was a piece of shit. Spec was absolutely no help either. I made many calls to them and had the clutch bled several times at their request but it was still a piece of shit. Tossed it in the trash and put in a McLeod RST and had no further troubles.

I didn't have the same problem as the OP though, mine would not release at high rpm. Shifted fine at low rpm but anything over 5K and it was like the shifter hit a brick wall. The clutch just wouldn't release.

 

[JeremyH]

Please expond on your response. Also, I see you post your dyno numbers but do you have any track seat time? You know it is very different street to strip.
.

Yeap been to the track many times. Havent had the turbo setup there yet as its only been done for a few weeks. With a couple bolt-ons last summer me in my 4000lb vert i ran a 13.7 @ 104mph with a 2.3 60ft on street tires on a 90 degree day. How is it different? When i launch and romp on it on the street its the same thing i do at the track. As long as you let the clutch cool down between runs, the clutch doesnt know wether your on a city street or a track lol. I will agree if you are running stickier tires doing massive burnouts and hotlapping then yes the clutch may take more abuse at the track.

Im just telling you what i have learned from other peoples issues, i can think of half dozen times just off the top of my head of spec clutch failures in our cars. Be it noise, multiple slave failures, shifting issues etc. If you want more detailed info im sure eventualy those guys will post here or do a search for spec and you will find the more detailed info you seek.

And judging from your sig, rip second clutch, maybe you are a little worse for wear on clutches lol, I cant count how many times i powershifted and did 4-5K dumps on my stock clutch with no issues before i swapped it out and i never hot lapped the car, always let it cool.

Hopefully yours was just too hot and that big hit of torque in a bottle didnt do any permanent damage, good luck, let us know the results when you test it out again.

 

[1fastpony]

Yeah...it was almost an hr between runs and could get the engine halfway cooled down with the eh20 pump but you know that drive train was still hot. And, going from a 2.xx 60' to a sub 1.8 60' is a worlds of difference, sub 1.6 60' even more.

I have heard that others have had similiar issues in the heat if you do not have a top dollar clutch.

 

[1fastpony]

What kind of cltucth related symptoms will you get with bad or mixed hydraulic fluid?

Startin to consider maybe the hydraulic fluid maybe the issue. Think some Synthetic Dot 3 was installed with other type. When the car sits awhile hot and its hot down here now I will get the same problem. I can rev the car up in rpm and you will feel the clutch pedal get soft. let the peddle out slowly or quick and it will slip. you can drive around and it doesn't act up even when going WOT at a dig or roll, no slip. To put it simply, the clutch will act just like the brake peddle when over heated, go soft or instantaniously pulse..kinda crazy but maybo not.

Passes 4th aanf 5th gear low rpm full throttle test.

Whats the best fluid beside the DOT 3 HP the manual calls out?
Whats the best way to fully purge the old fluid out?

 

[aleborjas]

single disc exedy thats it!

 

[1fastpony]

single disc exedy thats it!

I would think it was the clutch but it has only three passes on it. I'm just curious if something else is causing the problem. The CF DFC clutch had a problem with walking at high rpm on the starting line occasionally.The peddle even got soft but not as bad. Eventually failed on the pressure plate side and tore all the material off. The flywheel side of the clutch was just fine both clutch and flywheel surfaces.

This didn't show up till the hot weather. I'm just thinking if the similiar symptoms are present as with the other clutch maybe it's some other part not doing its job.

1. Slave HTOB?
2. Bad or Hydraulic fluid boiling or air in line?