Need help. BAD VIBRATION
I'm hoping that someone can shed some light on a very bad vibration that my Cobra has developed.
It starts about 2700 rpm in 5th. (or about 4500 in 4th) and gets worse as you gain MPH or RPM's. If you shove in the clutch, the vibration gets worse. If you shift into neutral the vib. gets worst.
The vibration is so bad at 3000 in 5th, it's like sitting on a vibrator. The vibration sounds like a phasing vibration until you get up to 3000 then it's just bad.
Here's what I've done to date. Installed the following items
Throw out bearing
Turned Fly wheel
Installed a loaner tranny
New universals, straighten and balanced drive line
new axels with bearings
replaced all bearings in 3rd member, 4:10's look good.
New tires, even installed my brothers wheels & tires but the vibration does not improve.
I'm wondering if maybe I have a bad pinion angle, or need to replace any rear bushing?
The car has the following. 5.0 supercharged, 90mm mass air. 30 # injectors, Mac equal length headers, 3" off road H-pipe,3" cat-backs, F-303 cam, APE Chip, Smog pump eliminator, Center force dual friction clutch & pressure plate, T-5 tranny, stock driveline, 4:10 gears, Eiback lowering springs, sub-frame connectors welded in place, lifting rails welded into place. '98 Cobra rims, 275/45 ZR17 Dulop tires about 1000 miles on tires.
Any help would be great.