GXP FE3 Suspension not the FE3 from ZOK as advertise by GM

[RobL]

I didn't actually read that people turned the TC AND the ESC off (holding the TC button for 5-8 seconds). Have people done this before doing their tests?

(pardon me now - I have to put some Hoosiers on the car for an event tomorrow)

[SolsticeMan]

Well, all due respect to LV, I have to disagree somewhat.

Fortunately I have been afforded back to back rides of stock base solstices and stock GXPs. My opinion only, but the GXP is better controlled at high speeds, it turns in better, settles better in corners. This is 2007 vs. 2007 cars, and also a SKY thrown in for good measure.

The GXP (and/or RedLine), (again my opinion, and I don't own my own of either) to me seems to have a neutral turn in, obviously less roll in a hard corner, and mild understeer exiting corners. I think (again, MY OPINION) that this is a proper way to set up a car that has excess accelerative capability. It allows the ability to roll on throttle without worrying as much about countersteering. The ability to trim the car with throttle was nice, and the lag which I was worried about was mostly non-existent.

Skidpad/stopwatch showed pretty much identical lateral g's - about 0.88 to 0.90, some on same day, some on different days, and mostly on the same location. Approximate speeds through a slalom, about 65-69 mph on average for a base solstice on stock tires, and about 2 mph faster and more consistent on a RedLine (GXP not available that day).

(the MX-5 that was loaned to me that day got a higher max lat, but a lower slalom speed, on Michelin preceda tires - the amount of roll in that car is shameful - AGAIN, MY OPINION)

My initial thoughts were that some more damping might be warranted in the rear of the GXP, but not sure if that would be worth any tradeoff in rough ride. It would also potentially hurt the neutrality of the turn in - making turn in 'sharper' but potentially more difficult to control, and corner exit more dicey when going with power up...

I was waiting for fastmike's chance to revalve shocks, 'cause I suspected he would add damping. Apparently it works, but also makes it ride harder. Ordered my ZOK/Clubsport Solstice today!

I bet it autocrosses better, but would be worse on a road course.

Conversely, the turn in of the base car seemed as neutral as the GXP, but the car seemed a teeny bit more... tail-happy on corner exit. I found that interesting, but factor in the amount of power and it isn't that surprising at all.

Again, MY OPINION, that people may be perceiving the amount of transient understeer tuned in the car as 'less handling'.


HOWEVER, there's more to handling than weight, power:weight ratio, stopping distance, and grip/skidpad g's. A car must also balance ALL directions of acceleration, and a driver must be able to read a car and find a way to live with it, bend it to his/her will by changing/tuning it, or find another 'weapon of choice'.

I also find that the further I push a GXP/RedLine, the better it feels - that means the closer I get to the edges of the friction circle, the better I feel. Just MY OPINION.

Now, IF I read this stuff right, people seem to feel the GXP is more 'pushy' or maybe isn't as 'sprightly' as the base car. To many, this is considered 'less handling'. Maybe I am misinterpreting it, but allow me contrast that with a car I consider 'sprightly'.

The Honda S2000. I don't know if any of you have driven one. Wicked-sharp turn in, but that car sometimes has a will of its own. Corner exit behavior - it all depends. Have you heel-toed and hit the right gear? What's your corner exit RPM, are you in the power band (about 6K) or below it... before, during or after the cams switch? if you're below it and the cams switch on you powering out of a turn - you had damn well be johnny-on-the-spot with the countersteer, or set up an appointment with any track 'safe barriers' and your rear fascia. Corner exit - not enough chassis understeer, and not a consistent torque application = tail-happy.

Be smooth in an S2000 - turn in must be done carefully and no quick corrections. Don't do anything more than what you intend - like in a chicane, and be PROMPT in your countersteers - or you will eat 2-second penalty cones for lunch. It sucks to try and pry them out of the wheel wells.

Does it handle 'better'? Yes. No. Maybe. It has better grip (0.92g) on stock tires. Slalom with active handling off is or can be a friggin' handful. You may squeeze an MPH more than the GXP, but you will work your ASS off to do it. I don't this this is the hallmark of a good-handling car - FOR ME. (this means: MY OPINION)

I enjoy driving the GXP/RedLine more.

What's your favorite color?


This all leaves us with what to do. From the added power alone, I find it hard to belive that a n/a Sol will negotiate an autcross or road course faster by the stopwatch than a GXP - ESPECIALLY if prepped with Hoosier/Kuhmo type tires. This has never happened in any of our evaluations.

But - as I said, power:weight isn't everything, either. Just look at the SCCA Solo Nationals - a 16.4 lbs/hp car stomped a 450 lb lighter 14.7 lbs/hp car. Go figure.


It seems to me we may not (LV's well-done evaluations aside for a moment) dealing with anything that can be put on paper, but maybe a necessary balance in a car with 55% more power and torque. I can't always borrow a VBOX or DL1, so I have to do my stuff the old fashioned way - with a stopwatch.

I hear these same 'complaints' at times about the Corvette. It doesn't 'feel' like it handles that well - but any car you can slam around Grattan Raceway in the sub minute-and-a-half timeframe sure as heck ain't a slouch.

[SolsticeMan]

Originally Posted by RobL I didn't actually read that people turned the TC AND the ESC off (holding the TC button for 5-8 seconds). Have people done this before doing their tests? (pardon me now - I have to put some Hoosiers on the car for an event tomorrow)

Most of the time, if I get to eval a car in a semi controlled environment, I certainly do any measurement with those systems shut off.

[LatinVenom]

The test were always done with them off (TC and ESC).
SM, my only observation is stock RSA's vs Stock GS2's and you and I know the GS2's are much better.
So my tests were done with the exact same tires, size and psi and the behavior of my 1st 1K N.A. car was always better than the same test on the GXP.
I had a question from you about the 22lbs that are no longer on the rear of the GXP and will this be the cause of the difference?.
Thanks for all your insight.

[jimbo]

S-Man,

Thanks a million for your clear, thorough response. I know you have a lot of seat time in both cars driving at or near the limit. As much as I respect birdliver's and LV's credibility, I have to go with the guy with the seat time.

That said, where there is smoke, there is fire. Bird, LV and todd raleigh all report the GXP does not handle as well as their old base cars. From that I know 2 things. The base cars felt like they handled better, even if they didn't and that counts to the owners. The base car is probably easier to drive. Being easier to drive it inspires more confidence, therefore in the mind of the owner, it must be better handling.

I don't want to get absurd, but if bird, LV and Todd jumped into a Porsche GT3 cup racer, I am pretty sure their butt dyno would tell them the GT3 doesn't handle as well as a base Solstice, because it would not be as easy to drive with that big V6 motor leaning up against the back bumper. But you and I both know, the GT3 would dust any Solstice in the handling department.

I guess I am lucky I never bought a base Sol. When I get my GXP, I won't know the go-cart feel I'm missing from the base car and it won't bother me at all.

Bird, LV, todd & others. Good luck with your cars. Sorry they don't feel as controllable or as responsive as the base car. Whether or not the cars handle as well is really of no matter if they don't feel like they handle as well.

Good luck...

[jimbo]

Originally Posted by LatinVenom I had a question from you about the 22lbs that are no longer on the rear of the GXP and will this be the cause of the difference?.

Go buy a 20 lb weight at a sporting good store and tape it down firmly in your trunk and let us know if it makes any difference. I would bet good money it won't. But try it and let us know if you can tell any difference at all.

[SolsticeMan]

Originally Posted by LatinVenom The test were always done with them off (TC and ESC). SM, my only observation is stock RSA's vs Stock GS2's and you and I know the GS2's are much better. So my tests were done with the exact same tires, size and psi and the behavior of my 1st 1K N.A. car was always better than the same test on the GXP. I had a question from you about the 22lbs that are no longer on the rear of the GXP and will this be the cause of the difference?. Thanks for all your insight.

We're replying back and forth in three different threads...

I thought I replied back about the weight, and turns out I did.

Gxp Z0k?

Originally Posted by jimbo S-Man, Thanks a million for your clear, thorough response. I know you have a lot of seat time in both cars driving at or near the limit. As much as I respect birdliver's and LV's credibility, I have to go with the guy with the seat time. ...

I wouldn't say a lot of seat time, it's just the seat time I do have is concentrated. I don't own a kappa, and every drive in one is in a car I don't personally own. This goes also for S2000's, Cobalts, Fusions, Civics, MX-5s, XLRs (man, are THOSE rare cars!), Corvettes, Porsches, BMWs and the like. I am subject to a) the ability to find one, and b) the inclination of an owner of one to let me drive/evaluate it, and c) figuring out the 'limits' and 'terms' allowed in that drive, respecting the owner's wishes. I own none of these, but to be a good vehicle dynamicist means that you MUST NOT be an electron driver. In my personal experience, it has never been the case where a math model EVER completely 'proved' anything.

Every major manufacturer from BMW to Ford to Toyota to GM to... EVERY major manufacture of vehicles, INCLUDING governments - ALL of them own or have access to a 'proving' ground.

Every major tire manufacturer does too. So do most if not all of the suppliers of stability control systems, such as Bosch (in Flatrock?). It all matters when the rubber meets the ground, and you can't tell a pizzant's leg about a car if you don't spend time accumulating driving experience in many cars.

I never, EVER want anyone to think I'm discounting bird's, LV's or anyone elses driving opinions - driving a car, especially an enthusiast car such as an S2000, MX-5, or Solstice, is a personal experience.

These guys have had a rare opportunity - to be able to back-2-back experience the OWNERSHIP experience (all the ups and downs) of having two different versions of Solstices, and their perceptions are very important. My opinion is exactly that - an opinon, it carries no more weight than these guys.

I'm just trying to figure out if there is something simple that might work to 'finetune' their car to meet their expectation. The open discussion also puts this in a public light for lurkers who might be doing the same wondering but choose not or can't participate.

[jimbo]

Originally Posted by SolsticeMan I wouldn't say a lot of seat time, it's just the seat time I do have is concentrated.

My point being that you appear to have seat time near or at the limit. Most of us, and I do mean almost every driver with a driver's licence from one of the 50 United States, has NEVER taken a car to its limit of adhesion in controlled circumstances, or driven a car at 10/10s.

Talking about how a car handles at 7/10s really doesn't have any meaning when folks say "my new car doesn't handle as well as my old car." All that means is, "my new car doesn't drive as easily or feel as stable under similar circumstances compared to my old car. So when people talk about how a Miata handles compared to a Solstice, I'm not really fit to say just because I've driven them both on the street at 7/10s. You on the other hand, have driven them both at 9/10s or 10/10s (to tire grip failure) with stop watch in hand. That is my point.

None of that, of course, is relevant to how an owner feels about how his car handles. For al intents and purposes, under the driving I do every day, if one car feels like it handles better than another, then IT DOES handle better than another, in my world view and experience.

For LV, bird and Todd, for all intents and purposes, their GXPs do not handle as well as their previous base cars. They and I are probably using the term "better handling" in 2 different ways. They clearly mean they liked the way their base Solstices handled better. Period. Nothing matters beyond that. I'm using the term to mean, if Don Knowles drove their base cars vs. their new GXPs on a street race circuit, through chicanes, which car would have a lower limit, which car would run off the race course at the lower speed?

Anyway, I still very highly value your sharing your experiences and opinions on this subject. It is important to me, anyway.

Originally Posted by SolsticeMan I never, EVER want anyone to think I'm discounting bird's, LV's or anyone elses driving opinions - driving a car, especially an enthusiast car such as an S2000, MX-5, or Solstice, is a personal experience. These guys have had a rare opportunity - to be able to back-2-back experience the OWNERSHIP experience (all the ups and downs) of having two different versions of Solstices, and their perceptions are very important. My opinion is exactly that - an opinon, it carries no more weight than these guys.

That is why I highly respect their feelings. They know what they know. It is like AztekzRpurty having a bad clunk in his car and someone else saying "mine doesn't clunk at all". LV, Bird and Todd know what they know. I haven't owned either car so I don't know jack.

Their comments indicate one of 2 things. Either the GXP doesn't handle as well as the base Solstilce or the GXP doesn't feel like it handles as well. It will be interesting if we ever find out which is the case.

[Krazed Kanary]

IMHO This discussion is becoming moot until someone actually tests both cars under the same conditions with accurate data aquistion.
AFA perception, each has their own standards which are wholy subjective. In which case, no matter what, you can never please all the people all the time.
I know when I go to my dealer and talk with the sales reps and service techs virtually all of them who have driven a GXP when asked directly admit to being intimidated by the GXP's additional power. I wonder how much affect being intimidated by it, even subconsciously, colors the perceived handling. A non competition trained driver I'd expect would rate the handling of a base Mini Cooper above a ZO6, simply because the Cooper is extremely predictable and planted giving lots of feedback and warning yet sporty and nimble in it's handling, whereas it is pretty easy to get a ZO6 out of shape with just a small wrong twitch. It's all a matter of comfort level, not actual capabilities.

[jimbo]

Originally Posted by Krazed Kanary IMHO This discussion is becoming moot until someone actually tests both cars under the same conditions with accurate data aquistion. AFA perception, each has their own standards which are wholy subjective. In which case, no matter what, you can never please all the people all the time.

I just feel sorry for birdliver, LV and Todd. They loved their old cars' handling. They love their new cars' power. They are just trying to get both in the same package. I understand where they are coming from.

In my heart of hearts, I agree with you about adding power to a car. It becomes an entirely new ballgame and that power really commands respect and your driving must reflect that respect. I can definitely see where adding so much power to a car could influence anyone's perception about a car's handling.

On the other hand, only those people who actually owned a base Solstice and now own a GXP have the 1st hand knowledge. The rest of us are merely speculating.

[JUSTICE]

Originally Posted by Krazed Kanary IMHO This discussion is becoming moot until someone actually tests both cars under the same conditions with accurate data aquistion. AFA perception, each has their own standards which are wholy subjective. In which case, no matter what, you can never please all the people all the time.

Isn't that what all the magazines did when they came up with the GXP numbers? They tested both cars under similar conditions and all the mags showed lower lateral acceleration for the GXP than for the base Sol. Now I know the skidpad isn't the all encompassing measure for handling, but it is a part of it. You would like to think the performance trim level of this car, which has more power, would also handle better, not worse, heck not even equal. Some of it might be just personal preference of how it subjectively feels. Maybe the setups are just different, but not necessarily "better" or "worse" and some like one different over the other. In either case, for this car, not only do you have factual data showing the GXP doesn't handle as well, or at least a component of it, but you also have some pretty educated drivers who have driven both cars, saying on average that the base car handles better. Something is not right. Lucky for me, I'm almost happy I never drove a base model, that way I wouldn't be disappointed with the GXP. I also don't think it should have anything to do with how good of a driver you are, how fast you've driven, how experienced you are, or how much you've raced on a track. This is about principle. If I'm paying more money for a performance version, it should perform better, even if I never take my car sideways, it should be there anyway.

[SolAnderson]

Originally Posted by JUSTICE .... This is about principle. If I'm paying more money for a performance version, it should perform better....

It does perform better. It's a LOT faster/quicker. For only what was it? $3-4k more with additional upgrades thrown in.
I'm happy

But, When one of our cohorts here on the forums figures out the trick to get the susp dialed in/improved, I'll be copying him/them. In the meantime I'll work on learning what the limits on the current setup are and how to work them to advantage.

[Krazed Kanary]

Originally Posted by JUSTICE I also don't think it should have anything to do with how good of a driver you are, how fast you've driven, how experienced you are, or how much you've raced on a track. This is about principle. If I'm paying more money for a performance version, it should perform better, even if I never take my car sideways, it should be there anyway.

But how would you know if it did or not? If someone put you in the seat of an Indy car and sent you off to drive it 0-60MPH on the street, do you really believe you could tell how well it handled? I'd bet the first time you pushed a little too hard on the gas or jerked the wheel in a turn or worse touched the brake in a turn and it jumped around backwards you'd be screaming the thing doesn't handle worth a hill of beans. The better a car handles, the harder it is to drive without getting into trouble. A a rule of thumb, the higher the performance potential of the car the more likely the factory will hobble it with gobs of understeer off the assembly line to keep neophyte Mario wannabes around long enough to be future customers. I was highly disappointed with our GXP's feel on the highway until I had it re aligned and changed to stickier street tires, but even then I now have a nasty dent in the rocker panel where I took out the finish timing light during a demo run at an AX school I was instructing. I mistakenly left the (new) street tires on the car and it unexpectedly got away from me, a problem we never had with the same tires on our much lower powered previous cars. My wife who was also instructing also spun it a little while later in almost the exact same spot, but she ended up doing some off roading rather than hitting anything. We will NEVER try to drive the car at it's full potential on steet tires again! Does that mean the GXP's handling is worse than our Celica or Miata? No, not hardly, it was just the wrong tire to get the maximum handling potential on an AX course out of the GXP!

[JUSTICE]

You are either saying the GXP handles better, or you are missing my point. Also, someone who has owned both the base and GXP, and has driven with them with both the stock tires and with the same aftermarket tires on both cars, is saying the GXP handles worse with the aftermarket tires then the base model did with the same tires. If the back end is breaking loose easier on the GXP wouldn't that indicate the suspension setup is providing less grip, otherwise it would hold the road. Yes, there is more horsepower as well, so if there were no suspension changes I would suspect it could handle sloppier at times. But there are changes, and those suspension changes should reflect the power increase so the car at least handles the same as the base model, not worse. Of course Indy cars are harder to control, so is a Viper, etc. But I get the feeling GM didn't intend for the GXP to be harder to control than the base model or to respond more like a Viper.

[VTXSTi]

I have owned both the NA & GXP but have not taken either to the track so I have not taken either car to their limits. I have done spirited driving on the twisty back roads. I have felt the rear of the GXP kicking out when accelerating out of a turn but have attributed it to the additional power not poor handling. On occasion I drive a cloverleaf ramp to see how well the car tracks and to see what speed I can achieve without exceeding my comfort level and I can reach a higher speed in the GPX then the NA. I do not have a handling issue with either car but the issue addressed in this post may be at higher speed levels then I have reached.