RedBullRR

iTrader: (7)

Well my break in period is over on my Exedy Stage 1 Clutch and ACT Streetlite flywheel.

For some reason when I rev past 4K RPM, thru 5K RPM I hear this nice humming noise. Kind of like a supercharger spooling.

Any thoughts on what this could be? It doesn't effect or hinder performance. I'm wondering if it is due to the lighter flywheel or maybe belts are humming. Not sure what it is but need some input/help.

Biochem7

iTrader: (8)

I thinking of going with that flywheel over the prolite. How's the chatter and driveability?

RedBullRR

iTrader: (7)

The chatter is there but very very low. Actually I think my stock was a bit louder. You do here some chatter when taking off, but thats due to the fact that you just removed the dual mass flywheel. This flywheel has a dampener built into it.

Personally I love the setup, best money spent for the Z so far.

06MagneticZ

iTrader: (13)

I keep hearing ppl talking about the chatter not being too bad, but my JWT flywheel is way too freakin' loud. It makes my mirror vibrate at certain rpm's. I might have to get it checked out. Maybe this isnt normal.

RedBullRR

iTrader: (7)

I hear the JWT is the loudest. Witch is why I steered away. I went with the Exedy because they make the clutch for JWT JWT just puts there name on it. As for the flywheel I went with the Streetlite vs the prolitet, probably the quitest of them all from what I read.

To be honest I was expecting chatter. But I didnt get what people reported. I do have this humming sound that sounds good, just not sure if it should.

RedBullRR

iTrader: (7)

Bump! Anyone?

jonnylaw

iTrader: (3)

Do you have stock lsd/rear end and stock final gear or have you swapped those out?

RedBullRR

iTrader: (7)

Stock VLSD. Everything other then the Intake/Clutch/Flywheel is stock.

I have noticed my belts need to be replaced sooner then later. But would this cause that wine?

jonnylaw

iTrader: (3)

hmmm. I was gonna say it could be gear whine if you recently installed a new gear set or lsd. It's possible the belts could be causing the noise at a higher rpm, but dunno. Might be a good idea to replace them for maintenance reasons anyways, see if the whine persists, and go from there? Sorry I can't offer more advice. Maybe someone with more experience can chime in.

SuperBlack350z

iTrader: (59)

you can try to change the belts but i doubt that's it. The belts are easy. I switched both of them in 10 minutes. You just have to go down teh list of possible things and eliminate them.

n1sm0r

iTrader: (3)

Sounds like your pressure plate isn't balance. Not really a big deal at all, 99% of car's have pressure plates that aren't 100% balanced. I'm guessing you can actually hear yours because your flywheel probably doesn't absorb the vibration very well since it's a lightened one.

I wouldn't worry about it, just enjoy!

RedBullRR

iTrader: (7)

I took a video yesterday of the humming noise, and the "Chatter" everyone speaks of. As you can see the chatter isn't a problem at all. The humming noise sounds pretty cool, just want to make sure its not going to be a problem.

Well here is a vid with the humming and "chatter"

And another vid with the "chatter" outside the car and inside.

VTS

iTrader: (1)

I would be interested in knowing what causes this as well. I have that same humming noise at about the same rpm but it is not nearly that loud. You can only hear it in mine if you rev it while in neutral. If you are driving under a load, the exhaust drowns it out. I have the ACT prolite flywheel by the way.

RedBullRR

iTrader: (7)

Bump for a clear understanding why?

jonnylaw

iTrader: (3)

whoa-that humming noise is kinda weird. But it kinda sounds like harmonic resonance--maybe its just the lightweight flywheel not absorbing as much resonance as the stock dual-mass, or the pressure plate not being 100% balanced as others have said.

RedBullRR

iTrader: (7)

It is kinda of weird, everyone i put in my car always says man that sounds sweet. But it wasnt there before the break in period. Seems it got louder once it broke in. The sound doesnt hinder performance, nor does it sound like something breaking. Just wondering what it is, before I ask my mechanic.

RedBullRR

iTrader: (7)

Bump!

mAKERSmARK

How many miles on your Z? I have seen counter shaft bearings make a similiar noise in the upper RPM range. If the noise duplicates in neutral, you may have an input shaft bearing issue as it rotates regardless of clutch engagement or gear.

SuperBlack350z

iTrader: (59)

one question, was this installed by yourself or did a shop do it?

frizille

iTrader: (3)

I got the same chatter/whine @ 4k. Competition Clutch stage 4 w/ 14lb fly. Curious as to why as well (but it sounds cool).