Car handles terrible at high speeds. All over the road. Scary. Need Help.

[77tech9]

I doubt my car can do over 140

thats why never pick a race with a 5 speed ls1 ...

 

[Buick Mark]

I remember reading these cars were capable or 146 mph in stock form without any speed limiting in the computer. Due to tire design at the time and aerodynamics, GM felt 120 or so was safer. These cars are rockets and damn fast, BUT the body design was for your Mom, Dad or Aunt to go shopping, yes, its much more aerodynamic than the body designs that preceded it, but its no 'Vette or F-body. Do the best you can do as far as tightening up the suspension, but respect the tremendious power the Buick V-6 turbo puts out and remember the handling (or lack of) traits of your car. Its normal for a car, turbo or not, to get sideways on wet or dry pavement, my 71 GS 350 does the same thing, its the degree of angle of the road for water drainage off the road surface, plus trucks, busses, etc, that put divets in roadway, the slighest angle or lean in the road surface can make any car slew sideways Mark

 

[david buschur]

In my opinion, having driven tons of high performance cars, the GN/T-type is one poor handling high speed car.

I have yet to drive one with stock suspension on it that didn't feel exactly how you are describing.

I have a 37,000 mile WE4, it was all over the place at anything over 85 mph on hard acceleration. After buying the car, rebuilding the engine, trans and body of the car I was super disapointed in the handling.

I installed a set of Eiback Pro springs and Koni shocks all the way around. I had also installed a set of airbags in the car. I had to run them around 3 psi in both to keep the 10" wide BFG drag radials from scraping. This helped with the rear sway the car had some. The car was still super loose in the rear.

I bought HR Parts n Stuff complete rear suspension kit at the National last year. Over the winter I installed it all.

I had the car out a few weeks ago on our first nice of day of year here in Ohio. The airbags are now completely flat in the car (no air in them)

The difference in the car is night and day. It no longer rubs the tires in bad spots in the road, even without any air. The handling at high speeds is what I would consider good now. The car has NO sway in the rear at all. The cornering is now super tight, it doesn't feel like any other GN/T-type I have driven.

The quality of the parts were top notch. The sway bar design is like what you find on a real drag car, it no longer just attaches to just the control arms, it ties into the upper frame of the car.

I noticed after a hard launch on the car I hit about 130 mph. The car was super stable and no longer scary feeling. I slowed down and was just cruising, when I looked at the speedo I was still doing 90 mph on a not so good road. The car has never been stable like this.

As a side note the parts I took off the car were in perfect conditions. All the bushings and such were still fairly pliable as they were when new, nothing worn or sloppy.

The suspension kit, wasn't cheap, I don't remember what I paid for it. It is also not "cheap" when you get it. Super high quality, everything was nicely gloss black powder coated, high end urathane bushings in all of it, nice stuff.

Might want to consider this for yourself you are really tired of the cars handling.

David Buschur
racer, car builder/owner.

 

[87gnblackdemon]

How about front end suspension when coming to a rather quick stop? Doing about 45mph on a side road and then coming to a quick stop at a stop sign. The steering wheel shakes quite nicely, and front drivers side wheel feels as if it's shaking as well. I've been told this could be my rotors. Others have told me to jack the car up and try and push in and out on that wheel, cause it could be a bad wheel cylinder.

 

[UNGN]

Originally posted by 87gnblackdemon
How about front end suspension when coming to a rather quick stop? Doing about 45mph on a side road and then coming to a quick stop at a stop sign. The steering wheel shakes quite nicely, and front drivers side wheel feels as if it's shaking as well. I've been told this could be my rotors. Others have told me to jack the car up and try and push in and out on that wheel, cause it could be a bad wheel cylinder.

This sounds like a cooked passenger side upper control arm bushing. Even my 24K mile GN has this problem (while my 90K+ mile T-type with polygraphite bushings does not)

Good springs, shocks and bushings will make the car not so scary at speed. Running 165+ in my Grand Prix is no big deal, so there is nothing wrong with the chassis design.

 

[d0n_3d]

Originally posted by MistaScott
Where are you going 90MPH and getting away with it?

The few times I've gone over 90 the car has handled like crap. TRs are notorious for it and the brakes are hardly capable of stopping the thing. Scariest time of my life was trying to stop from 120 MPH.

Check your bushings and maybe add the GNX bushing in addition to what has already been suggested.

i tried stopping my GN after a 130 mph run after racing a crotch rocket and i had to stop within a short distance and i had my brakes to the floor and i could smell them burning...talk about scary sh!t...i was watching my life flash before my eyes

 

[d0n_3d]

Originally posted by 87gnblackdemon
How about front end suspension when coming to a rather quick stop? Doing about 45mph on a side road and then coming to a quick stop at a stop sign. The steering wheel shakes quite nicely, and front drivers side wheel feels as if it's shaking as well. I've been told this could be my rotors. Others have told me to jack the car up and try and push in and out on that wheel, cause it could be a bad wheel cylinder.

on that vibration problem...my 99 f-150 4x4 truck does the same exact thing...it's a common problem with those trucks...the cause is warped front rotors...if you catch it early, all you need is for them to be turned...if too late they need replacing...