|
|
|
|
| Author |
|
|
Formerly bb80sc
Join Date: Aug 2001
Location: Hollywood Beach, CA
Posts: 4,361
|
'Harmonic shudder' at 90mph?
Hello all, so my car gets a really odd 'harmonic' kind of shudder/vibration that starts at about 90mph and gets worse. It's unnerving at the track for sure. My wheel bearings all appear to be fine, checked and tightened the fronts a bit. Tire balance should be good, they were done not too long ago. Any other ideas? Flywheel? Clutch? The car has a very worked over suspension with new components. The vibration/shudder does not seem to come from the front because the steering wheel does not shake.
TIA -B
__________________
Cheers -Brad 2015 Cayman GTS 2015 4Runner Limited |
||
06-07-2009, 09:40 PM
|
|
|
Registered
Join Date: Jan 2003
Location: Algonquin, Illinois
Posts: 696
|
I used to have something like that on my SC. I installed pop-out rear quarter windows, what a difference! No buffetting, no noise, even at 125mph. Also expeienced the same thing my '91 Vanagon, had the front door windows closed, side windows open. I thought a helicopter had landed on the roof!
__________________
PCA-Chicago Region-DE Tech Coordinator-Retired PCA-Chicago Region GingerMan DE Co-Chair-Retired 1987 Cab-under construction-Sold pending pickup 1986 911- Race/DE car-Sold |
||
|
06-08-2009, 02:33 AM
|
|
|
Formerly bb80sc
Join Date: Aug 2001
Location: Hollywood Beach, CA
Posts: 4,361
|
Interesting on the wind buffeting. I can definately feel it 'in' the car. I think it may be a tire/wheel issue after all. I'm going to a local place with the state of the art Hunter system which will match and balance the tires and rims.
__________________
Cheers -Brad 2015 Cayman GTS 2015 4Runner Limited |
||
|
06-08-2009, 07:28 AM
|
|
|
Registered
Join Date: May 2003
Posts: 3,346
|
My car gets this when the tires are shaved out of round or they have flatspots. If possible trade tires with someone for a session.
-Andy
__________________
72 Carrera RS replica, Spec 911 racer |
||
|
06-08-2009, 10:35 PM
|
|
