Bouncy 2003 Nissan 350z
 

Hey so I just recently purchased my first 350z and I absolutely love driving this beast. I have owned it for about 3 weeks now and the suspension is super bouncy, a soft kind of bounce and it can get pretty bad in high speed if i go through a little bump. I don't know a lot about suspensions but from what i've heard its my shocks that are done. I searched up some shocks for my car and found KYB Excel-G twin tube struts any opinions on how well it performs? I am just looking to ride smoother and a bit stiffer since the bounces some times turns my slip light on the dash. I am on somewhat of a budget since I am in Uni and cant afford the best products out there
when i bought the car it came lowered, I am not sure if its on lowering springs or cutted springs. definitely not coil overs.
and another thing my seat slides back wards, reclines back and forward fine but the forward slider doesn't work any suggestion?
Thanks!

Get stock suspension. It's most likely bouncing due to cheap aftermarket coils

If your budget is tight, replace the springs.

If you have more room in your budget, replace the springs and the shocks.

Look at the springs and see if you can see a name on them. Post pics of them if you can

It sounds like your shocks have lost their dampening ability. Is the problem at all four corners, or specific to one area?(front, back, left or right) - Try pushing down on each corner independently with slight force. It should bounce back up, then settle; not bounce one more cycle. Since you're on a budget, I also think you should go back to OEM. It's better to spend a couple hundred on OEM than be forced to buy from the cheaper end of aftermarket for the equivalent price. As far as your seat, I'm not too sure. The sliding rail could be bent or pinched, limiting its forward movement. Look under there with a flashlight and check it out. It's hard to say from here. :twocents:

You didn't mention how many miles on the shocks/car.

I mentioned this about a week ago in another thread:

"...if you're on stock '03 suspension, bear in mind that Nissan screwed the pooch (excuse me for that... only way to describe) on the '03-04.5 shock/spring combination. Very "jolty" and not at all a balanced nor smooth ride. That was corrected in '04.5 models forward as they either softened the shocks or altered the spring rate (can't remember exactly which)."

To support EYEgor 350's (Atreyu'Z) :icon17: comment and based on this fact, the BEST solution for your '03 is to replace both shocks AND springs. HOWEVER, if budget doesn't allow this, replace the shocks only as they are the single biggest influencing factor on the ride quality (or lack thereof.) Keep in mind that the shocks' sole duty is to control the spring oscillations.

Replacing the springs only will do little to improve the ride if the shocks are bad. But, as terrasmak mentioned, try to identify or post pics of the springs because if they are not original, they may be overly stiff aftermarket units... in which case, new shocks will help only marginally.

On your considered choice of KYB GR-2s (AKA "Excel-G", same shock), well, couple of things... these are "stock replacement" quality only. They will help "some" if you are on OEM springs. They are NOT meant to be paired with aftermarket lowering/high rate springs and will not last if pushed beyond design limits.

A better choice - within a higher but still relatively reasonable price range - are Tokico HP (AKA Tok "Blues") shocks. These are designed from the get-go as performance replacements which work fine with both stock and aftermarket springs. They are also specifically valved for the Z. There's only about an $80-100 difference between them (based on a quick check of one of our vendor sites.) Personally, if this were me, I'd wait and save up for the Blues as this choice today will carry you many years for better/worse.

PS By the way, the "bounce test" prescribed in this thread is largely a myth (or at least way outdated). Strut type suspensions all "feel" OK when doing this because of high spring rates to start (vs. "conventional", really old school non-indep coil/leaf/torsion bar suspension like on a '68 Dodge Dart..heh heh). Only thing the bounce test is good for on a Z is testing the strength and elasticity of your fenders. Laff...... :p