Evo Pilot

iTrader: (1)

Hello,

I am hoping that someone could help shed some light on my problem.

Car
08 GSR @ 4800 mi with Eibach prokit springs and eibach front and rear sway bars. Everything else is stock except for the wheels.

Problem
When the car is put into heavy load / full boost in 4th gear between 3200 and 4500 rpm, I have a vibration that can be felt in the shifter the gas pedal and the steering wheel momentarily. the vibration can also be felt on the floor by the passengers The vibration stops after 4500 rpm. This is not a speed or wheel balance related issue because it only happens under heavy load on the motor. None of this was occuring prior to the spring and sway bar install. The wheels where installed later with factory tires. Wheel change had no effect. The car has been properly aligned at the time of install.

I have since been back to my local suspesion experts to check all bolts and alignment. Everything checks out. The technician thought that a may be driveline related.

I want to get this sorted out before I begin making more power. As I am sure that will only make it worse.

Any help would be appreciated.

Thanks

flyguycfi

iTrader: (4)

Have you launched hard much? Autocross? Any hard driving much?

Wish I had an answer for ya, but a vibration is pretty generic. Maybe someone else will have some input.

EndlessRed

iTrader: (17)

um, what about after install.

Evo Pilot

iTrader: (1)

The car has not been auto crossed or launched.

It was aligned after the suspesion was installed. The alignment was checked again on my second visit

EndlessRed

iTrader: (17)

tuned? your car might as well be just hesitating.

Evo Pilot

iTrader: (1)

As the first post states the car is stock excect for the suspension. The car is not hesitating. As the it reads this all began after suspension changes. Let me know if you have any input on drive line vibrations. After the suspension has been changed.

Thanks

wongck

iTrader: (4)

does this only happen in 4th gear are the stated RPMs, or all gears at those RPMs?

qJai

did you make sure you tighten your swaybar endlinks fully? similar thing happened to me, tightened em, n now no more.

Evo Pilot

iTrader: (1)

The vibration is occuring in all 5 gears it is the most noticable in higher gears at lower RPMs. I have checked the sway bars and end links and found them all to be installed correctly and torqued down.

aj_pierce

you just dropped your ride with a different style spring then stock, your definitely going to feel something. Might even be the tighter suspension with both front and rear bars there fore transferring more road turbulence or hell the bars are attached to the chassis could even be from the motor. Vibration is way too generic

Evo Pilot

iTrader: (1)

Ok Ok... This is not my first or second EVO I have had 2 VIII's both with sways and springs or coilovers and now the EVO X. This is not the first time I have modified the suspension on an EVO or other sports car platforms. It is the first time I have ever felt vibration in the gas pedal, the floor or the wheel under heavy load / Boost after a new suspension was installed. As far as the vibration being to vague. I have described it in good detail. If there is a peice of information that is missing that will help diagnose this issue just ask and I can tell you. I think that I may have an issue with a CV joint or possibly a U-joint in the driveshaft. I am leaning more to the CV do to it having a steeper angle after the suspension. I am curious if any other members have had similar issues.

tr3flip

Please contact Dave or Phong from the R&D department at Eibach. They should be able to help diagnose your problem. The number there is 951.256.8300 and just ask for either one of them.

-Tony

aj_pierce

Different car, different platform. Might even be a defect in one of the aftermarket parts. Your guess is better than mine.

sonicrx

tight or slighlty stick u- joint in the drive shaft can cause this exact issue. have you checked them?. cv joint will not do this well you would have to drop more than 4-5" for a cv to do this ,and it would happen all the time not just at a certain rpm. certified tech for 12 years ,and specialized in drivability,and drivetrain

Evo Pilot

iTrader: (1)

Thanks,

This is the type of information I am looking for. I will pull the driveshaft out and inspect the u-joints and carrier bearings This weekend. The only odd thing would be that the carrier or u- joint angles would not have changed through the suspension install. I will find out this weekend and let you know. Anything else you can think of to check while I have it up on a lift ?