vroom_vroom

iTrader: (5)

This car (any car) is such a money pit! Just the bushings alone will keep you busy for a while

vroom_vroom

iTrader: (5)

This car (any car) is such a money pit! Just the bushings alone will keep you busy for a while

BudRacing

iTrader: (3)

With the voodoo carrier, toe rods, trailing arm, and cradle bushings, it will be very taut. Had you been able to drive them back to back, you'd be blown away. I was surprised how much the carrier support alone took up the slack during shifting/acceleration. Much better now. I did these mods one at a time, so it will be night and day with the full setup. I should have done it all years ago!

jmilz28

iTrader: (13)

I actually did drive it after the voodoo carrier, just not over 40 bc of vibes from the newly unbalanced shaft. It definitely improved it and was immediately apparent. Also apparent is that the remaining clunks were from that pos flywheel. Can't wait!!

jmilz28

iTrader: (13)

**** this motherfucking car. After all that, it even vibrates like hell in neutral. Really bad between 2-3k. I got the flywheel and PP balanced, my guy said he lined the marks up, and it vibrates. First the driveshaft...I gotta buy a new driveshaft with a POS center support, now the damn thing shudders like my 95 SBC with a shitty flywheel. I hate this ******* car. $3500 in parts and labor and it's not smooth and not driveable above 40. ****!!!

Anthony Toal

sorry to hear this boss, what size flywheel did you go with?

jmilz28

iTrader: (13)

Factory LS7 flywheel, steel. I even paid to have it balanced...
28lb maybe? Far less than the 40lb dual mass POS which was coming apart, so it was time.

Anthony Toal

mine is 27lb from monster, i dont think it is a balancing issue, what I believe made a big difference is a tranny rebuild. They had to replace the bearings and machine the shafts, it made a HUGE difference. It just seem common,and Bud as stated this, that every time someone replaces the clutch or the 2 pc DS, there is a vibe and I think that is because, one, less rotational mass = more harmonics and two, you are directly changing any characteristic of a vibration that could have been there but was masked I would also maybe double check the guys work, the whole Trust, But Verify thing, ya know

vroom_vroom

iTrader: (5)

So it's doing it when moving (coasting) in neutral? I wouldn't Jump right for a 1k plus part. I would venture to say they didn't balance the shaft correctly.

jmilz28

iTrader: (13)

I know the driveshaft needs to be balanced but that's a known and separate issue. The new vibe is the car sitting still, trans in neutral. It's worst at 2-3k. Definitely not the driveshaft. What in the transmission spins when it's not in gear, main input shaft?

Yeah, lining up the balancing marks and star pattern torquing/trust but verify totally occurred to me. Frankly, so did the bolts and clutch disc that were not part of the balancing...

I'm also wondering if this is all just why GM used that dual mass fly in the first place. Then again if so, why not on the LS6 Z06 vette?

vroom_vroom

iTrader: (5)

Sorry if my questions seem stupid or redundant but I'm late to the party and perplexed with you,

So the car is not moving so no speed vibe but the vibes are solely based on rpm do you still get them if the clutch is pushed in? That should rule out the trans parts,

Any chance you have a pulley that took a crap, balancer or some other issue that could be non clutch related?

voodoochikin04

iTrader: (3)

Vroom.... Jimz got our diy kit and had issues with the CV joints while doing the changeover. He had a shop reassemble the driveshaft but is pretty sure they have it clocked wrong so the balance is off.. that's one vibe issue He is dealing with... The second is the clutch vibe in neutral from 2-3k rpms.. basically...
fiasco.

vroom_vroom

iTrader: (5)

That's what I'm gathering. Any chance the shop that did the clutch will take on the issue?

Drive shaft can be balanced. Not a huge deal if you can find someone close. I'm sure I'm not telling you anything you don't already know......

ls1247

iTrader: (2)

there have been several reports of the v1 ls6 cars have thus vibration...I had it to varying degree in both ls6 cars I've had...

the vette damper is different by design than the v1 damper so maybe that has something to do with it...who knows.

Anthony Toal

I thought the reason why the put the dual mass flywheel in the V is for creature comforts? I thought they were targeting a crowd that wanted the luxury with some of the performance and they did this to help control the rpm and keep that Cadillac smoothness, I dont think it had to do anything with vibes. If it is just doing it in neutral, I would assume it is from the rotary assembly to the input shaft.

jmilz28

iTrader: (13)

It's proving difficult to balance our 2 piece shafts but I have one or two more places to call before buying another unit of some flavor.

I just put a Fluidampr on it while it was in getting the clutch replaced. I haven't eyeballed it while revving but it appears silky smooth and straight at idle. I was trying to get ahead of this vibe issue.

Even in neutral or with clutch in, the input shaft and counter shaft are always spinning. My assometer tells me the vibes are closer to the engine than the trans but I wouldn't bet my life on it. The ARP bolts and clutch plate itself were not involved in the balancing so I guess that could have thrown it off. I also can't verify with my own eyes that the bolts were torqued correctly and balance marks aligned but I do trust my guy a good bit. He really cut me a deal on this job, think half, so I hate to lean into this too much, especially with a clutch kit from a different car. Had I paid normal rate on the original part, it would already be back on his lift. Rockauto has Luk OEM parts back in stock, and I am considering that dual mass going back on for the smoothness. I hate to lose the quicker revs I have now but these vibes will cause issues in the long run.

I do keep thinking about why GM used the dual mass in the first place. I also wonder about the fact that I have pulled 12-15 lbs off the rear of the cranks shaft and added a few to the front. That's gotta affect the balance doesn't it?

BudRacing

iTrader: (3)

I'm surprised to hear with a Fluidampr that the vibes during free revving are that bad. I currently have a 167k OE LS6 dampener and the C6 clutch setup with ~70k on it. It's not the smoothest thing, but it's definitely not bad. I have an ATI dampener ready to go on when I get the time.

jmilz28

iTrader: (13)

Well, I confirmed with an aeronautical engineeer that changing the weights on both ends of the crank, flywheel and damper, WILL change the balance.

BudRacing

iTrader: (3)

So do you think the fluidampr did more harm than good? From the reviews I've seen on the product, everyone has seemed pretty happy with them. The theory behind its design seems pretty sound.

Anthony Toal

Wrong
I am just an "electrical" engineer, but i took the same physic classes for static and dynamics masses.

"Since the harmonic dampener (front) or flywheel (rear) play a part in the balancing of the assembly, they must be installed on the crankshaft when it is balanced. This is unlike an internal balance configuration where the harmonic dampener or flywheel do not contribute to the balance of the crankshaft and are not required to be installed when the crankshaft if balanced. Both methods are used from the manufacturer."
http://www.enginebuildermag.com/2009...aft-balancing/
Unless it is a major difference, it shouldnt be that bad, this may help explain some

Just changing the flywheel/clutch and dampener shouldn't give you the issues unless the dual mass was absorbing a lot of it. The internal balance rotary should handle minor changes without effecting over all balance. I also dont think the bolts should be causing that much of a unbalancing issue either due to how close they are to the center of the flywheel

If this was true, when changing either one or the other, meaning the flywheel/clutch or the dampener, a lot more people would have vibe issues