I own an 86 rx7 gxl, 129k miles it is in fairly good shape. It had the automatic adjust suspension. The ride was getting pretty poor so I replaced the shocks and struts with non-adjustable KYB's. I was expecting a much better ride and slightly improved handling. What I got was about the same ride and slightly better handling. The car still slams hard over bumps and will damn near rattle my teeth out on the highway during bad sections. I am at my wits end. I just spent $360.00 on shocks and there is little to no difference. So my question is this, what else could it be? I know that my sway bar bushings are bad, but I never thought they would make that big of a difference. Cold it be my springs? Can springs even go bad? I am going to have a little bit of money from my tax return and am hoping to fix this problem, any assistence would be much appreciated.

 

If your car is shaking at high speeds then its the tires, they are probably out of balance or need replacing. It could also be u need an alignment too.

I replaced the tires on my 240sx and got 4 wheel alignment and it made the car drive smooth all the way up to its top speed without any shaking (120mph)

 

For openers - ride quality is very subjective.
For example stiff for a sedan is normal for a sports car.

There are other variables, but the big one is - tire pressure.
Maybe you're running the pressure a little too high for your shock/spring/sway bar/tire size combination.

My prior NA was lowered about 3/4" and it ran best with 29PSI in the fronts & 27PSI in the rears.

 

ok sorry for the lack of information. the car is completely stock aside from the shocks and struts. I had a four wheel alignment performed right after they were installed. I still have the stock wheels with stock sized winter tires that are at 30 psi all the way around that were just balanced and installed less than two months ago. The car does not pull while driving or vibrate at high speeds, just very very poor ride quality over bumps etc. there are times in the snow that it gets a little scary because the car jumps around so much it is hard to control. I know that I shouldn't expect a Lexus lke ride and I never will, I just want it to not wander as much when the road is rough and not rattle my teeth out and have to hear my girlfriends constant complaining. I was expecting a ride like this after it was lowered, but not before with reasonably good shocks and stock springs. My old 87 gxl rode way better than this and I am just trying to hunt down the culprit. My only guesses are that the springs don't 'match' the struts and shocks, or that the bushings are so far gone I just need to bite the bullet and replace them. I figured I would put it to the experts first before I go and start throwing my money away. Thanks again

 

would too much negative camber also cause the car to shake?

 

I am having the same exact problem. I noticed this thread just ended with no real explaination or advice. Anymore help anybody can offer?

 

tires, tire pressure, suspension bushings, and worn springs and struts all will effect ride.

 

springs,
I have a 90 gxl, I think I have lost a few fillings from my teeth in hwy 14 between Ann Arbor, MI.
Springs? new springs softer springs? anyone else upgraded their AAS to aftermarkets with good results?