Spec 2+ Slipping already?
Thread Starter
Safety Car
Joined: Dec 2001
Posts: 4,295
Likes: 2
From: Indianapolis Indiana
Cruise-In III Veteran
Cruise-In IV Veteran
Spec 2+ Slipping already?
Well, long story short I estimate my car to be at 420rwhp and had went through 2 Z06 clutches, and at the advice of a shop went with the Spec 2+, as it was supposedly not the best clutch, but was light and would *definitely* live forever at my power level.
The clutch was installed by the shop and had some chatter issues, but did get better after 500miles, though it always needed a lot of revs to take off. I became used to it and looked at the bright side that it really did rev nice and made for great heel-toes.
Well, out of nowhere after only about 10months and 10k miles it started slipping. NOW I'm disappointed, but maybe I'm just in the norm with my Spec experience.
Questions:
1) Did anyone else have a spec start slipping under light duty? I ran some track days last summer, but it started slipping out of nowhere last month.
2) If so, is the clutch done, is the flywheel done, are there any quick fixes?
Thanks!
The clutch was installed by the shop and had some chatter issues, but did get better after 500miles, though it always needed a lot of revs to take off. I became used to it and looked at the bright side that it really did rev nice and made for great heel-toes.
Well, out of nowhere after only about 10months and 10k miles it started slipping. NOW I'm disappointed, but maybe I'm just in the norm with my Spec experience.
Questions:
1) Did anyone else have a spec start slipping under light duty? I ran some track days last summer, but it started slipping out of nowhere last month.
2) If so, is the clutch done, is the flywheel done, are there any quick fixes?
Thanks!
Le Mans Master
Joined: Dec 2005
Posts: 8,475
Likes: 332
From: Port Arthur, Texas 77642
I don't have the Spec clutch but I have an RPS with problems. Once the clutch starts slipping repeatedly under hard acceleration it is worthless. I have an RPS that is slipping now with only 1000 miles on it. I can't say for sure, but I believe if I would have done the "Drill Mod" that I may be enjoying driving my car now instead of waiting to buy a new clutch. A very well respected tuner has told me they do this mod with EVERY clutch install, just for some added assurance the clutch will not slip. Read the link, it makes sense. I know many, many C5's owners have installed clutches without doing this, but to borrow a line from the movie "Casino": a Mobb Boss says "why take a chance". The slave cylinder is out already so just do the mod, it will just take a few minutes. Aftermarket clutches are a strange breed, seems many have a personality of their own. Good Luck Bro 
http://www.vetteweb.com/tech/vemp_05...all/index.html
http://www.vetteweb.com/tech/vemp_05...all/index.html
Thread Starter
Safety Car
Joined: Dec 2001
Posts: 4,295
Likes: 2
From: Indianapolis Indiana
Cruise-In III Veteran
Cruise-In IV Veteran
I haven't slipped it much. Maybe 5-10 times total...it took 5 before I realized it wasn't wheel hop, but now it's just plain slipping. I could reproduce it anytime over 4k rpm in any gear over 3rd, but don't want to finish the clutch off. I assume it's probably junk either way. What about the pressure plate?
I'll definitely look into the drill mod.
I'll definitely look into the drill mod.
Le Mans Master
Joined: Dec 2005
Posts: 8,475
Likes: 332
From: Port Arthur, Texas 77642
I haven't slipped it much. Maybe 5-10 times total...it took 5 before I realized it wasn't wheel hop, but now it's just plain slipping. I could reproduce it anytime over 4k rpm in any gear over 3rd, but don't want to finish the clutch off. I assume it's probably junk either way. What about the pressure plate?
I'll definitely look into the drill mod.
I'll definitely look into the drill mod.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Fidanza now has a line of clutches out for our cars, I am currently looking at them but the Cobra guys seem to like them. They don't have much history though from what I can find. Pressure plate appears to be made for them by Valeo, one of the largest manufacturers in the world who makes 1/2 the european clutch systems. Just throwing this out as an additional option not too many guys are aware of.
Safety Car
Joined: Jan 2001
Posts: 3,879
Likes: 3
From: Hobart, WI
The LS7 clutch seems fine except for the disc. In fact the LS2 and LS7 use the same flywheel and pressure plate but different disc. The LS2/7 flywheel and pressure plate offers more pressure but the disc is average. We need aftermarket clutches based on the later fw and pp. I see Fidanza is now offering them.
Last edited by see5; Jan 23, 2007 at 08:45 AM.
Drifting
Joined: Dec 2005
Posts: 1,720
Likes: 3
From: East Hampton CT
This is specifically what I was worried about and why I went with Textrailia. I initally wanted a Cartek but they were backordered for a few months at the time so I went with Textrailia. ZERO slipping with 412rwhp and any abuse I can throw at it.
Safety Car
Joined: Jan 2001
Posts: 3,879
Likes: 3
From: Hobart, WI
I have been on a Cartek now for couple years and it seems fine. Most recently ~ 480 RW and lots of torque.
We just put a LS7 clutch in a LS1>LS7 buildup but but the discs are known to fry.
Vettenuts put me onto this and I found it quite educational:
http://videos.streetfire.net/video/0...aa00fe0ac1.htm
The Cartek is bronze/ceramic they say. I am used to it but others who drive my car have a helluva time with it.
We just put a LS7 clutch in a LS1>LS7 buildup but but the discs are known to fry.
Vettenuts put me onto this and I found it quite educational:
http://videos.streetfire.net/video/0...aa00fe0ac1.htm
The Cartek is bronze/ceramic they say. I am used to it but others who drive my car have a helluva time with it.
Last edited by see5; Jan 23, 2007 at 01:55 PM.
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Advanced
Joined: Sep 2004
Posts: 56
Likes: 2
From: Plant City Fl
I had the same problem with the Spec II Plus about a year ago. With less than 2000 miles on it, it started to slip under hard accelaration. I have about the same RWHP as you and was told by a Rep.from SPEC that it would be fine. Needless to say, when I contacted them about the clutche and the problem I was having, I was "blown off". I broke it in properly and had over 400 miles on it before any agressive or hard accelaration. After about 8 weeks of frustration 
talking with SPEC, I had the clutche removed and replaced with another brand. My first and last experience with a SPEC CLUTCHES.
talking with SPEC, I had the clutche removed and replaced with another brand. My first and last experience with a SPEC CLUTCHES.
Former Vendor
Joined: Feb 2004
Posts: 9,615
Likes: 13
From: Burlington NC
One other little tip and thing to look at before you start spending more money. Make sure your fuild level is down just a little from the top. I have seen people fill all the way up and when things get hot,(headers) there is no room for the fluid to go, so it pushes the clutch in just a bit. If that doesn't work, you clutch is junk.
Randy
Randy
Thread Starter
Safety Car
Joined: Dec 2001
Posts: 4,295
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From: Indianapolis Indiana
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Former Vendor
Joined: Jun 2002
Posts: 2,045
Likes: 3
From: Bridgewater Ma
The SPEC 2 shouldn't be used for anything over 380rwhp.It will slip as you found out. A 3+ should of been used and it drives the same.We also see a ton of bad installs.If the stock slave is used there is a shim that has to be removed when replacing the throw out bearing.About 90% of the installers miss this and it put's pressure on the PP which causes the clutch a short life.
Racer
Joined: Apr 2005
Posts: 279
Likes: 0
From: bluffton sc
I have had good luck with the ram metallic/organic clutch. It never chatters, and lasted a whole year with about 10 trips to the track on a 530 rwhp car with 28" slicks. I had one in my car for over a year when it had 450 rwhp.
Thread Starter
Safety Car
Joined: Dec 2001
Posts: 4,295
Likes: 2
From: Indianapolis Indiana
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Cruise-In IV Veteran
The SPEC 2 shouldn't be used for anything over 380rwhp.It will slip as you found out. A 3+ should of been used and it drives the same.We also see a ton of bad installs.If the stock slave is used there is a shim that has to be removed when replacing the throw out bearing.About 90% of the installers miss this and it put's pressure on the PP which causes the clutch a short life.
Can my aluminum spec flywheel be used again? If so, would it work with other brands of clutches? I really am not happy with SPEC, but the low price and potential to keep the flywheel might make me come back. I'm just trying to assess if it was a junk clutch (purchased new), bad install, or if i did something (though i wasn't too hard on it, and it died at a time I wasn't driving hard at all).
I paid to have a show (part of a dealership) that specializes in corvettes do the install. That being said, I wasn't 100% confident in the particular person who did the install. I'll definitely inspect to see if that shim was removed on install. This shop sells and installs Spec clutches and shouldn't miss something like that. It chattered pretty bad on install, but got better after 500miles. Still, there were always bad sounds when it was disengaged.
Do you have a picture of the shim in question so I can ID it?
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
I have been clutch shopping for a few weeks and the number of people complaining about the SPEC clutches is overwhelming. I won't even consider them at this point. The two I am looking at now are the Fidanza (available in about a month or so for LSx vehicles) and the clutchmasters series 300 which the guys over on LS2.com seem to be having very good luck with. The Cobra guys have been having favorable reviews of the Fidinza clutches.
Melting Slicks
Joined: May 2004
Posts: 2,502
Likes: 4
From: cincinnati ohio
I am seeing some awful skeptical assessments of your problem Brody.......I have got your PM, but why dont you give me a call tomorrow....... Anything leaking on it ????
I seriously doubt someone forgot to take a shim out, hell someone should have added two more shims his pedal hieght was so low when first installed.................... SPEC actually supplies shims to go under the clutch actuator assy..... drill mod does nothing for a slipping clutch unless the pedal/actuator for some reson is not returning.
Did you buy the clutch directly from SPEC, or someone else, I dont remember.......I just remember you having a clutch whe you arrived. Do you have the lightened aluminum pressure plate ???
Talk to you tomorrow, dont forget to call............
I seriously doubt someone forgot to take a shim out, hell someone should have added two more shims his pedal hieght was so low when first installed.................... SPEC actually supplies shims to go under the clutch actuator assy..... drill mod does nothing for a slipping clutch unless the pedal/actuator for some reson is not returning.
Did you buy the clutch directly from SPEC, or someone else, I dont remember.......I just remember you having a clutch whe you arrived. Do you have the lightened aluminum pressure plate ???
Talk to you tomorrow, dont forget to call............