Clutch problems with your stroker 6-speed?
Thread Starter
Intermediate
Joined: May 2011
Posts: 36
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From: Jax. FL
Clutch problems with your stroker 6-speed?
anyone experience vibration after replacing the Dual Mass Fly Wheel. Suggestions for a replacement. My Fidanza sounds like a very loud box of rocks.
Race Director
Joined: Nov 2003
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From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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That's a common complaint after converting from a DMF to SMF. Did you change to a sprung-hub clutch? If so, a SPEC FW is considered the best SMF alternative at this point (because of it's heavier weight).
Or, seek out a used DMF unit. Lower mileage and/or newest specimens are probably your best bet.
Or, seek out a used DMF unit. Lower mileage and/or newest specimens are probably your best bet.
Race Director
Joined: Apr 2000
Posts: 15,344
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From: Texas
...and yes, if you use a single mass flywheel (even with the sprung hub), you get lots of noise at idle with the clutch engaged/tranny in neutral, as well as while accelerating thru the first few gears.
Thread Starter
Intermediate
Joined: May 2011
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From: Jax. FL
Thanks, I sold my low mileage DMF (cheap) on the advice of my builder. Said it would not handle the high torque of the 383. Can ZF Doc provide an economical remedy the solution, without rebuilding the transmission? Curious.
Thread Starter
Intermediate
Joined: May 2011
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From: Jax. FL
The engine was built incorporating an internally balanced forged rotating assembly. So, to answer the question, no we did not add weights to the fidanza (may be a problem).
What clutch and flywheel combinations do you guys run. To your knowledge, which produce the greatest success rate?
Guys, thank you very much for your help. I appreciate it!
What clutch and flywheel combinations do you guys run. To your knowledge, which produce the greatest success rate?
Guys, thank you very much for your help. I appreciate it!
Le Mans Master
Joined: Mar 2001
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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St. Jude Donor '12
My installer told me a story about someone that put a lighter weight flywheel and it made a horrendus noise and vibration with clutch out and in neutral.
Mine with a heavier flywheel does not make near as much noise, still a "rocks in the can" rattle with the clutch in and in neutral.
I get a lot of vibration at 4k RPM, think I've narrowed it down to a bad engine mount. going to try solid mounts next if I can find them.
Mine with a heavier flywheel does not make near as much noise, still a "rocks in the can" rattle with the clutch in and in neutral.
I get a lot of vibration at 4k RPM, think I've narrowed it down to a bad engine mount. going to try solid mounts next if I can find them.
Burning Brakes
Joined: Nov 2010
Posts: 1,006
Likes: 2
From: Spartanburg South Carolina
my car does the same thing also. Had a SMF in there with the black tag and it sounded just like your describing. I freaked at first thought i had bought a lemon car but soon found out after reading on zfdocs site that this was normal. THe new setup i have will be very similar hto yours. Fully forged 396, new SMF and a sprung hub spec 3+ clutch. We'll see how that sounds
Race Director
Joined: Apr 2000
Posts: 15,344
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From: Texas
The engine was built incorporating an internally balanced forged rotating assembly. So, to answer the question, no we did not add weights to the fidanza (may be a problem).
What clutch and flywheel combinations do you guys run. To your knowledge, which produce the greatest success rate?
Guys, thank you very much for your help. I appreciate it!
What clutch and flywheel combinations do you guys run. To your knowledge, which produce the greatest success rate?
Guys, thank you very much for your help. I appreciate it!
With a single mass flywheel (SMF), some vibration/noise is normal. Based on your first post, I'd say that there's not an issue. If you used a clutch disc with a solid hub (vs a hub with springs), it'll be even worse. Moving to a sprung hub will help a little. Moving to a heavier flywheel will help a little more. To get rid of it completely, you need to go back to the dual mass flywheel setup.
FWIW, I use a SPEC steel SMF setup with my 383. Definitely a "box of rocks" at idle
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Thread Starter
Intermediate
Joined: May 2011
Posts: 36
Likes: 0
From: Jax. FL
I've found out that my builder used chinese parts (t/o bearing and pressure plate). Not his fault, I'm told that the OEM replacement parts are very hard to find for the LTX. Parts that are readily available from the regular parts suppliers (including GM) are the chinese duplicates. I found a source that has some of the good stuff. PM me for information.
The clutch kit includes: Valeo LT4 racing pressure plate, Carolina Clutch Stage 2 sprung friction disc, INA clutch release bearing, Valeo clutch release bearing retainer, GM Performance fluted pilot bearing, and clutch installation tool.
The clutch kit includes: Valeo LT4 racing pressure plate, Carolina Clutch Stage 2 sprung friction disc, INA clutch release bearing, Valeo clutch release bearing retainer, GM Performance fluted pilot bearing, and clutch installation tool.
Last edited by 94LT1Z07; May 23, 2011 at 05:23 PM. Reason: add
Safety Car
Joined: May 2002
Posts: 4,659
Likes: 82
From: Toronto ontario
I built a solid roller 388 and used an aluminum flywheel with a McLeod street twin. It was loud, but the exhaust was loud too and so was the solid roller valvetrain. I had to run a high idle (900-1100) anyways so it was bearable. A few times I heard it at a rough 700 idle and I just laughed.
Did I have vibrations? Yeah just a little at about 4k that i could feel through the shifter but it stopped after my ac compressor exploded the first time I tookit to 8000 rpm. My new build uses an even lighter aluminum flywheel that has been drilled as well. I also have the new ac delete pulley lol
Did I have vibrations? Yeah just a little at about 4k that i could feel through the shifter but it stopped after my ac compressor exploded the first time I tookit to 8000 rpm. My new build uses an even lighter aluminum flywheel that has been drilled as well. I also have the new ac delete pulley lol
Last edited by 5abivt; May 23, 2011 at 07:43 PM.
Drifting
Joined: Aug 2000
Posts: 1,614
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From: Colleyville Texas
Went thru numerous other clutches before this set up.
Safety Car
Joined: May 2002
Posts: 4,659
Likes: 82
From: Toronto ontario
I agree with cruisin. For me I had tried to build a light weight motor capable of revving so it didn't make sense to keep a 44 lb flywheel bolted to the crank vs an 11 lb one. If I built a stroker for torque without trying to be lightweight the dual mass would have stayed for sure.
One of my favourite motors of all time. Check out the flywheel on this thing . Driving this car with this motor was my inspiration for building a high rpm revver !! I will hate torquey motors forever!!
One of my favourite motors of all time. Check out the flywheel on this thing . Driving this car with this motor was my inspiration for building a high rpm revver !! I will hate torquey motors forever!!
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
I recall that mine made noise until 2300rpm, then was gone, it was mostly loud at idle in neutral, but with my foot on the clutch is wasn't terrible, just annoying...
After getting tired of exorbitant clutch and flywheel prices, I bought the TKO 600,, the TKO 600 would be perfect if it had a 6th gear, but I only used 6th gear at 80+mph, which I hardly would ever do,
so for me it was a good move, I got an equivalent or stronger tranny, top quality clutch components for the same or less than the cost of a ZF flywheel and it uses all of my stock 1985 parts, TOB, hydraulics etc.
best of all, no rocks-n-a-box sound
After getting tired of exorbitant clutch and flywheel prices, I bought the TKO 600,, the TKO 600 would be perfect if it had a 6th gear, but I only used 6th gear at 80+mph, which I hardly would ever do,
so for me it was a good move, I got an equivalent or stronger tranny, top quality clutch components for the same or less than the cost of a ZF flywheel and it uses all of my stock 1985 parts, TOB, hydraulics etc.
best of all, no rocks-n-a-box sound
Race Director
Joined: Sep 2001
Posts: 14,685
Likes: 753
From: NEwhere Ohio
Spec stage 3+ sprung hub, lightweight fidanza aluminum flywheel, blue tag zf in my 93.
No issues with objectionable noise/vibration. There is a slight amt if you aren't driving correctly (ie. Lugging it in too high of a gear up a hill), but none otherwise.
Is it possible blue tag vs. Black tag makes a diff?
Not sure why everyone thinks heavy mass flywheels are best. Hotrod showed once that all startng line gains from a heavy flywheel are negated and exceeded by a lightweight flywheel by the end of the race. Net winner is the lightweight flywheel
No issues with objectionable noise/vibration. There is a slight amt if you aren't driving correctly (ie. Lugging it in too high of a gear up a hill), but none otherwise.
Is it possible blue tag vs. Black tag makes a diff?
Not sure why everyone thinks heavy mass flywheels are best. Hotrod showed once that all startng line gains from a heavy flywheel are negated and exceeded by a lightweight flywheel by the end of the race. Net winner is the lightweight flywheel
