OK, now I'm concerned
Thread Starter
Intermediate
Joined: Mar 2011
Posts: 41
Likes: 0
From: Bowling Green Kentucky
OK, now I'm concerned
In many earlier posts where dual mass vs. single mass flywheels and clutches were discussed, the SPEC kits were often mentioned as a good choice for replacing the old dual mass systems. I'm having the extra mass flywheel and stage 1 clutch from SPEC installed now. I don't race or burn out my tires and was just hoping this change out would eliminate the idle knock I was getting from my DM. With the recent threads, I'm now concerned. How many out there are running with a SPEC set up? How has it performed for you? Ease a fella's mind, please!!! 
Le Mans Master
Joined: Mar 2001
Posts: 7,999
Likes: 14
From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
Calm down. IIRC the heavy mass spec flywheel is ZF6/Corvette specific.
Measure twice before you install it.
The stage I kit should be fine. My mechanic had no issues with my single mass and stage I clutch.
Measure twice before you install it.
The stage I kit should be fine. My mechanic had no issues with my single mass and stage I clutch.
Burning Brakes
Joined: Sep 2008
Posts: 810
Likes: 58
From: Alva Florida
I ordered the stage 1 kit from Tom at carolina clutch. No rattle at all. I was soooo concerned like you, that I didn't use the transmission for 4 to 5 years. I finally got up the nerve when I was assured that it would be similar to stock. I even have a lopey cam which should have made the problem worse.
Order it as a complete kit, and you will be fine.
It won't be cheap though.
Order it as a complete kit, and you will be fine.
It won't be cheap though.
Burning Brakes
Joined: Mar 2009
Posts: 830
Likes: 6
Ok, I guess I am the dissenting opinion. I installed the complete kit, steel flywheel and it bangs and sounds like a fork in the blender at idel and below 1500rpm. Above that no problem.
If you don't race it, would imagine you'll be fine. Mine on the other hand has been crap. 4 months in and it started to slip. Now almost a year later (5k miles) it's getting pulled. I do auto cross and there are probably 40 hard full throttle 1st to 2nd shifts per month and a few dozen drag strip starts at Pro Solo per year. I installed it before the 2010 Pro Solo and ran it in the 2011 Pro Solo as well. Mine was professionally installed. When it gets hot it really slips.
As you can see by searching it's about 50/50.
If you don't race it, would imagine you'll be fine. Mine on the other hand has been crap. 4 months in and it started to slip. Now almost a year later (5k miles) it's getting pulled. I do auto cross and there are probably 40 hard full throttle 1st to 2nd shifts per month and a few dozen drag strip starts at Pro Solo per year. I installed it before the 2010 Pro Solo and ran it in the 2011 Pro Solo as well. Mine was professionally installed. When it gets hot it really slips.
As you can see by searching it's about 50/50.
Le Mans Master
Joined: May 2005
Posts: 7,362
Likes: 2,281
From: Central Maryland
I installed a Spec Stage 2 clutch kit, with extra-weight billet steel SMF in my '94 last year. I haven't put a lot of miles on it yet, but so far, it's working flawlessly, and I have no gear rattle at idle.
Live well,
SJW
Live well,
SJW
Le Mans Master
Joined: Mar 2001
Posts: 7,999
Likes: 14
From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
Ok, I guess I am the dissenting opinion. I installed the complete kit, steel flywheel and it bangs and sounds like a fork in the blender at idel and below 1500rpm. Above that no problem.
If you don't race it, would imagine you'll be fine. Mine on the other hand has been crap. 4 months in and it started to slip. Now almost a year later (5k miles) it's getting pulled. I do auto cross and there are probably 40 hard full throttle 1st to 2nd shifts per month and a few dozen drag strip starts at Pro Solo per year. I installed it before the 2010 Pro Solo and ran it in the 2011 Pro Solo as well. Mine was professionally installed. When it gets hot it really slips.
As you can see by searching it's about 50/50.
If you don't race it, would imagine you'll be fine. Mine on the other hand has been crap. 4 months in and it started to slip. Now almost a year later (5k miles) it's getting pulled. I do auto cross and there are probably 40 hard full throttle 1st to 2nd shifts per month and a few dozen drag strip starts at Pro Solo per year. I installed it before the 2010 Pro Solo and ran it in the 2011 Pro Solo as well. Mine was professionally installed. When it gets hot it really slips.
As you can see by searching it's about 50/50.
No my flywheel is not the heavy DM replacement and its a race car so I expected some noise. But the level of noise is such that I'd even drive it on the street if I could.
Thread Starter
Intermediate
Joined: Mar 2011
Posts: 41
Likes: 0
From: Bowling Green Kentucky
Ok, got my car back yesterday late and took it on a 250 mile drive. I have a "shimmy" when I first take off, but after that it shifts fine. I've got a little of the "rocks in a can" noise at idle, in neutral and with the clutch out. Quiet with the clutch engaged. So I'm a little disappointed. Going back to the shop this afternoon to see about the grabbing/shimmy at take off. I was hoping for better. 
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Burning Brakes
Joined: Sep 2008
Posts: 810
Likes: 58
From: Alva Florida
Hmmm. Thats usually an indication that the flywheel needs to be milled and is not perfectly flat. The clutch engages, and as it does, it hits the "high" spots on the flywheel.
Hope I'm wrong.....
Might have to get the flywheel checked out.
Good Luck.
Hope I'm wrong.....
Might have to get the flywheel checked out.
Good Luck.
Thread Starter
Intermediate
Joined: Mar 2011
Posts: 41
Likes: 0
From: Bowling Green Kentucky
Eh, talked with mechanic and then called SPEC tech. Both said give it some time to break in. I'm one of those that can't do the work myself, so I guess I'll give it some miles and hope for the best! Can't afford another $500 labor bill right now!
Burning Brakes
Joined: Sep 2008
Posts: 810
Likes: 58
From: Alva Florida
Don't feel bad. I do all of the work to my cars (except computer tuning) and sometimes I wonder if I really save any money.
Then again, I cant leave well enough alone.
Hope your problem works itself out. I swapped out my 4+3 to a zf 6speed, and there was no vibration (chatter) at all.
Keep us posted..
Then again, I cant leave well enough alone.
Hope your problem works itself out. I swapped out my 4+3 to a zf 6speed, and there was no vibration (chatter) at all.
Keep us posted..