D'sNuts

iTrader: (5)

Hey guys,

I'm trying to diagnose a sound that is coming from the vehicle that increases in frequency under acceleration. 2007 350z with 175k. On the youtube vide, you'll see that the first pull is a baseline pull before Uprev tuning, all subsequent pulls are after tuning has begun. Tuner does not believe it's an issue with the tune, and we both agreed that the disruption came due to the nature of the stress during tuning on a dyno repeatedly to redline, may just be coincidental that the issue occurred during this time.

If you could please have a look and provide some input, I would greatly appreciate it.

CK_32

iTrader: (1)

What mods have you done?

It sounds to me like you're tires aren't balanced or they didn't set you up on the dyno correctly. Sounds like your car is bouncing on the rollers.

yosip1115

Does it do it off of the dyno now too?

D'sNuts

iTrader: (5)

It exists off the dyno as well which it didn't before. I notice it during regular highway/street driving under acceleration as a "wub wub wub" that increases in frequency a higher speeds and is very noticeable which rules out any concern that the vehicle was not fastened to the dyno properly.

Mods are just CAIs, HFCs, Dual Exhaust, and single mass flywheel flywheel.

yosip1115

Jack it up and check your rear wheel bearings

travlee

iTrader: (8)

this

yosip1115

I posted that literally as I was changing my bearings in the rear lol. Common failure point and dyno strap stresses don't help..
Don't remember if ops is a z33 or not but I went for 370z axles and one piece hub/bearings this time around

CK_32

iTrader: (1)

Yea I'm still going to say wheels are unbalanced or your wheel bearings.

yosip1115

Sooooo what was it