Of the multitude of light weight flywheel reviews done on my350z.com, one's that will NOT come up if you run a search since their search database will now only go back to 7/04, every single one I've seen mention's a negative change in idle sound quality. The often used description is "it sound's like sand and gravel is running around in the tranny". Even the Nismo unit, which lightens the least does it. I want on on my car for rev matching, but I detest that kind of idle sound quality just as much.

 

http://my350z.com/forum/showthread.p...n&pagenumber=2

Go there.

 

___BUMP___

Final word, anyone?

 

wow, yous guys are like hella smart and stuff

 

yeah, i mailed my pulley to someone...what happened with that? sorry, i forgot who i sent it to...

 

Much as we'd like to know for sure on this mod, I doubt there will be a final word any time soon.

Over the years, from my experience, this mod has been a very popular one, with good results. On the VQ, the results are less spectacular since hp increases on such a fine engine are scarce.

The increase is there, it seems, tho marginal, but whether issues arise long term from the pulleys' usage, only time will tell.

C.

 

I ran the full set on my CLS for 30000 miles and not a hint of anything going wrong.

I would have no problem putting these on the G and I wouldn't worry one bit about them.

 

has anyone experienced a difference in sound at idle w/using the pulley's? My car sounds a bit different at idle, it makes a tick tick tick sound that was fairly apparent right after installing the pulley's at my dealer. Is it normal to have a different sound at idle from using the UR pulleys? should i take it to the dealer to get it checked out?

 

Yep, if read some on my posts way back when, you'll see I mention increased engine noise at all rpms. You'll also experience a little more engine vibration. The noise and vibration are side-effects from not running the elastomer damper ring the stock pulley has.

 

OK should I put them on? Or should I just use them for pricey beer holders?

 

Well .....that settles it then!

I still don't know if the mod is worth anything....

But the one question I did come up with out of this whole thread is...

Who the hell buys a G35 for DRAG RACING??????
It is all about the curve carving for me!!!!!

 

ive had the full set of pulleys for close to 25k miles. only problem ive experienced was a squeaky belt but that was remedied quickly by adjusting the tensioner (that occurred probably 15k after installation). just did a blackstone analysis and everything came out clean. i dont and have not experienced any added noises in the engine bay, but i always have the radio turned up.

 

In my few years of customizing cars, I have owned 7 UR Pulleys and two custom ones that were built by a shop for me, and never had issues. Average dyno gains were between 4-7 hp, and I loved the mod on all of my Nissans/Infinities...so two thumbs up from me on the UDPs.....

 

Oh, and if you really love this thread, read the following book. I did, and was amazed.
Advanced Engine Technology by Heinz Heisler. If you really really really love reading incredibly complex ideas that are explored from certainly a professional (Heisler is the Head of Transportation Studies at The College of North West London, and is supported by SAE) point of view, this is the book for you. Heisler not only thoroughly examines a few interesting ideas, he proves his points with various tests. His discussion of amplitude of torsional vibration increasing with increases of distance away from the flywheel should not be missed by anyone who has any interest in anything that was said/discussed/argued in this thread.

 

Oh and I salute anyone who has put forth the effort to being an engineer or a scientist of any kind. I read this thread with much interest, its been very interesting, to say the least.