Two things:

I've only heard that "sand in the tranny" sound at idle. When I hold in the clutch or when the car's in gear you don't hear it.

Also, when I first started driving with the new flywheel I would hear honking noises when shifting from 1st to 2nd or from 2nd to 3rd. It's recently subsided, but every now and again I hear that honking noise. Sounds like somebody connect the flywheel to my horn, but other than those two sounds I haven't had any problems.

 

errr maybe they did? j/k
has anyone done any dynos with a recently installed flywheel ??

 

For what it's worth, you don't really get lightweight flywheels for power increases. You get them for the increase in responsiveness. Being able to shift much quicker (especially downshifting) is the main boon they provide. You might get a couple of horsepower, but that's not really the point of a lightened flywheel.

What Raceboy said up above is what sealed the deal for me:

"Strange thing is, I got this to allow the revs to come up faster on H/T downshifts when I blip the throttle, but now there is so little engine braking, you really don't need to H/T at all to downshift without lurching."

Once I get my Z, a flywheel will be way up there on my list. Nothing kills me more than downshifts while driving hard. My current car has a 28 pound flywheel and very poor pedal placement for heal-toe action. Fast downshifts are a pain in the butt.

 

LOL, I thought I was just imagining that honking noise!! Just a harmonic I guess.

 

Is this "Honking" noise audible outside of the car?
That is strange, I don't want people to think I'm honking at them when I'm just shifting.

Hehehhee

Victor

 

Nah, it's not that loud. Only people inside the compartment will be able to hear it.

 

Well I am having my tranny replaced. I am seriously considering JWT, JUN or Nismo. I've read the comments about sand and honking and I'm wondering if you guys have any more comments.

My car is a daily driver and I'm not certain I even want to do this but since the tranny is going to be down anyways, I'm hoping you folks will post more comments.

Thanks

 

This answers alot of your ?s i think, here it goes , this is from SCC.

"Our final tweak for this month isn't directly related to handling balance,but rather to responsiveness and a bit of out-of-the-hole speed. In a quest for smooth,quiet drivetrains that are strong enough to take relentless abuse, nissan has adopted duel-mass flywheels on all (both) its new engines.
Big, strong gearboxes like the one in the 350Z tend to rattle and groan like a UPS truck at low rpm. The noise comes from torsional vibrations originating from the surge of individual power strokes. A dual-mass flywheel separates the crankshaft and clutch sides of the flywheel by a set of springs. Using the power of math, nissan engineers chose appropriate spring rates and flywheel mass to damp out these vibrations, making the gearbox smooth and quiet and eliminating complaints from those who would whine about funny noises.
Unfortunately, that math also shows nissan engineers the Z flywheel has to be 25.5 pounds to damp things properly. That doesn't seem overly heavy when a quick zing of the throttle unleashes 274 lb-ft of torque, but when we replaced that 25 pounds with 13 pounds of jim wolf aluminum flywheel, we were amazed what we had been missing. next post

 

Free-revving in neutral is just silly now. The lighter flywheel frees horsepower once used for accelerating its 25 pounds. In high gears , the difference is negligible, but in first and second gear, where each mile per hour means many more revolutions of that 25-pound flywheel, the difference is surprising. Hard-driving fast shifts are now easier and smoother, but cruising around, revs actually drop so quickly between shifts that lazy gearwork makes you drive like a clutch monkey.
The gearbox does indeed make noises now. At idle and accelerating hard below 2000rpm, you would think something was wrong if you didn't know better, but since you put the flywheel in, you understand the noises. Above 2000 rpm, the gearbox is silent. The noise shouldn't translate into accelerated wear, by the way, it just sounds like it does.
Despite the reduced inertia, the Z is still easy to launch . you can still lug it at 500 rpm away from a stop. You can still accidentally start in third . Otherthan the noise, there is no downside, whatsoever.

 

The fatter tires, lighter flywheel , and more determined limited slip (they put a KAAZ on)added up to exactly the same quarter-mile time (14.0 seconds),but a higher trap speed (101.4 vs. 99.2). This suggests the lighter flywheel did free up some power, but the oversized Toyos offered less grip off the line than the stock tires. Indeed , the 0-60 time increasedfrom 5.8 to 5.9 seconds, suggesting something was lost at the launch."

Well thats the flwheel part sounds good to me . Im sorry i dont know how to put that in one post if it can be fixed please do.

 

thanks for taking the time to write that up for us.

Victor

 

Thank you very much for taking the time to post that krismax.

I'm remain, uncertain whether or not to do this for a daily driver. I have to make a decision soon and after reading your post, I'm thinking I'm might not want to do this modification.

I don't want the noise but I like the idea of freeing up response. It doesn't sound like I would gain much in accelleration except at ridiculously high speeds (when compared to daily driving). I'm using Proxies T1-S too and the grip is substantially better than stock so, that part of the post didn't make sense.

I think I need to read up more on this from third party sources. Thanks again for your post.

 

I found these:

http://www.sportcompactcarweb.com/pr...50z/index.html

http://www.europeancarweb.com/projec...bmw/index.html

I think I might experiment. Now I need to find a vendor that will sell the JWT flywheel at the best price.

 

mayb someone can give is some sound clips from inside and outside the car. i know i would appreciate it.

 

Don't worry. If you put a lightened flywheel in your car you will NOT sacrifice driveability. The clutch still feels very loose and very manageable. If you're worried about driveability then I would suggest you not get a heavy duty clutch; but getting a flywheel by itself is not going to cause any problems.

Also, I would record a sound file, but I don't have the proper equipment for it.

 

no prob; that was just something i threw out there.

 

Lots of good info in this thread. Based on what I've read, I'm probably going to put off the flywheel for now. Since it would be a stand alone tranny mod for me, I'm probably looking at close to $700 for part and install if I don't do it myself, right?

Got other things I'd rather do first. But I do have a question... if I pick up a flywheel, it will most likely be the JWT or JUN. Anybody know someplace I can buy these? I've been all over different 350Z parts websites and cannot find either of them.

Where? Cost? and delivery time (since I assume the JUN would have to come from Japan)? These would help a lot in making my final decision..

 

checkout sgpracing.com.

 

Best vendor price I've seen so far for the JWT. Thanks!

 

no prob. i guess i'm different, but i think i'm gonna buy a jun if i do one. i really wanna hear first hand what it sounds like. that just freaks me out.