Some of the reason for the G's stiff ride is because of the lightweight aluminum suspension components. While having light components is ideal for ultimate handling, the lightness can result is some impact harshness.

Another cause of the harshness and poor seat of the pants handling is the EL42 Turanza tires which I believe is OEM on the X and most any other 03/04 G without the Sport Package. Since my car was orginally from Iowa, the previous owner got the Sport package, but passed on the much better Goodyear summer rubber and went with the EL42s. Let's just say I can't wait till these tires wear out. These are the exact tires that came as OEM on my father's 04 Toyota Sienna minivan!!!! They're crappy on his Sienna too. The EL42s are known for 5 things:

1) Harsh ride
2) Bouncy and wallowy ride
3) No grip
4) Lots of squeal
5) Poor wet weather traction

Go to the Tirerack and read the personal reviews about these tires. They're horrible and the average rating is a 4 out 10 which means it's one the worst tires I've seen reviewed. I don't find the wet weather traction to be poor, but it's clear these tires are pretty crappy and ride harshly even though they're suppose to be cruising tires.

I think a lot of the G's lean and pogoing in the turns it related to these tires. Going with a good all season Z-rated tire will most likely improve ride quality and increase handling immensely because of the much stiff sidewalls. Ultimate stick and feel is related to mostly to the tires. Limiting roll helps handling somewhat, but not near the amount people think it does. It's the tires that make the real difference.

 

Personally I am not holding my breath for this. If you search the threads for this you'll find out just how long these have been "just around the corner".
I have spoken to two different people at Eibach being told once that they are in R&D and once that it won't happen because the number of X's out there, combined with the non-modding mentality of the average AWD buyer who is looking for security just doesn't add up to the type of sales volume they need to make them pay.

Both of these people admitted off the record they would probably be willing to Pro-kit an X, with one having done it personally.

But reading all this I can't help but wonder: There is a pro-kit for the FX. Would a combination of the two kits do it for us? A little expensive but.....

 

I hear you big daddy d as I have done searches and seen the discussions on this topic... At this point, all I can do is to keep calling and buy a set if they are ever available... I do not have an alternate solution at this time or know of any other springs specific for the X.

I want to get new wheels but want to wait until I have a way to get rid of some of that fender gap without compromising the ride...

That being said -- I have been through the same run around with Eibach in the past on releasing a spring for particular model and when everyone was about to give up, they released a product... While I am not holding my breath, I do maintain some hope.

 

Keep hope alive Harleydood. I, too, make the periodic call cos I know the only way these ever will come out is if Eibach perceives a market for these. I encourage everyone to call Eibach at 951.256.8300 and just ask "Are there any springs coming for the X". Post any info you receive.

Having said that I am mere days away from the application of new rims/rubber and so some form of bastardization is probably soon to follow.

 

Looking forward to hearing the news from Eibach about the X springs. Keep us informed.

 

With the front suspension design virtually lifted from the FX, I think this should work.

An adjustable rear sway would be nice too---I wouldn't want one for the front, as it pushes too much for my tastes already.

 

Do you mind elaborating a little.

I just don't see what aluminum suspension components have to do with ride harshness.
The aluminum parts are basically triangulation suport for the load bearing components.
They may have more or less flex, which relates to proper location of the load bearing components,
but how does that impact the function of the springs & shocks???

You may have a valid point, I just don't see it

 

The "x" car's suspension is actually firmer than the stock sedan's, but not quite as stiff as the Sport suspension.

I noticed a shockingly better road feel at the beginning, having come from softly-sprung domestic cars.

What did you drive before the X, if I may ask?

 

OK -- I just got off the phone with someone at Eibach -- who I evidently spoke with in the past but do not recall. I told you have I have been hounding them!!!

It's official: a NO GO on Eibach G35x springs. The contact I spoke with mentioned that there have been calls for them but not enough to justify the manufacturing costs...

So then I go into the suggestion of using the front springs from the FX35 ProLine kit and the rear springs from the G35RWD ProKit... He had the same concern that I do and that is weight distribution... Anyway, he suggested I leave a detailed message for the Technical team and that they would get back to me within a couple of hours... As I told him, if it is possible, then Eibach may have their packaging\marketing cut out for them for the X...

Stay tuned...

 

Ohhhhhhh. So giving the same tires as the rwd sedan, the X corners better than the stock rwd w/o sports?

 

It's kind of hard to explain, but here it goes. The suspension components, brakes, and wheels are unsprung weight. Making these components lighter often results in better handling, faster response, more composure over bumps, and if the components spin (brakes, wheels) you can also improve braking and acceleration. A downside is if the components are light and stiff they can have a tendency to transmit a bit more harshness and NVH. The FM suspension is a pretty hightech setup (multi-link F/R), especially for the price of the car. The downside is many of the suspension components are cast aluminum. That means they're both very strong and very light. When working on my G's suspension, I was amazed at how light everything was. I was use to working on my Maxima with heavy stamped steel control arms, iron steering knuckles and such.

A couple magazines have noted the ride harshness of the G, Z, and M platforms and they've all attributed some of the ride harshness to the lack of unsprung weight in the suspension and the overall beefy design of the trailing arms, A-arms, etc.

I find that my G with the Sport package rides about as stiffly on regular surfaces as my Maxima did on Koni yellows at 80% firmness, H&R springs, and subframe connectors. It's a sporty ride for sure. When I hit a bump in the G, it does a far better job of soaking up the impact than my Maxima did though. I think my G's ride will improve once I can get some better rubber on the wheels.

 

Thanks, I appreciate the explanation.
That does make sense now that you've shed a little more light on it.

I continue to marvel at the wealth of knowledge available through this site!
Thanks

 

I wish I could explain it better, but I know I'm leaving other things out. Don't take what I say as gospel I should have noted that usually when you make a structure more rigid, you reduce NVH hence the reason why many automakers strive for significantly stiffer frames and unibodys. Having a stiffer the chassis allows you to run a softer suspension and still generate great handling numbers while maintaining a nice an quiet ride. A perfect example is the C4 Vette vs the C5. The C4 has a buck board ride and the chassis was very bendy therefore GM had to make the suspension tuning really stiff to get a good handling. The C5 on the otherhand was far more rigid and GM could dial down the dampening and spring rates a lot and still have a better handling and riding car. Allowing the suspension to absorb the bumps is far better than having the chassis do it.

Why lighter and stiffer suspension components transmit a bit more NVH is hard for me to understand or explain. I'm sure someone can do a better job.

 

Like I said we gots to be hounding these guys. More calls = more product.


Harleydood please keep me informed on this issue. Like I said my 19" are more than likely able to go on this weekend and then I am really going to want to go full court press on the drop issue. Nice work on the gettin' on 'em and stayin' on 'em front. Wouldn't it be shocking though if this never occured to them?

 

http://www.mazda6tech.com/index.php?...d=16&Itemid=32

Unsprung Weight

Unsprung weight is the term used to describe weight that is not damped on the vehicle. The wheels, tires, brakes, and some suspension components are unsprung, whereas everything else is sprung.

Decreasing a car's unsprung weight will increase its sprung-to-unsprung weight ratio, and that directly leads to improved ride quality. When your tire hits a bump in the road it sends a shock upwards into the chassis that must be absorbed. If it is a 3G shock, then the the chassis must absorb three times its unsprung weight. This jolt will cause transfer into the chassis, which causes the unpleasant feeling caused by hitting a speed bump. Cars with stiffer springs and harder bushings transfer this jolt more directly, which is why they seem harsher.

If the car has 80lbs of unsprung weight per tire, than a 4G shock could send 320lbs of force upwards per tire. That's 640lbs per axle hitting you from below to be damped in just one or a few inches of suspension travel, which can be a lot. This is why some sports and most racing cars use forged suspension parts- it reduces unsprung weight, so the suspension does not need to counteract as large of a force. Dropping the unsprung weight by 25% (admittedly a difficult thing to do) would decrease the upward force the springs need to counteract by 160lbs per axle, which in turn can allow the use of slightly firmer springs (reducing body roll) without a degregation of the stock ride quality.