???

The S2k has one of the best chassis designs out there, especially for the money. I came from a hardtop '02 Mustang with full-length subframe connectors, and I was in disbelief the first time I drove an S2k.....beyond night and day difference. And it doesn't even have a f'ing roof.

 

I have no doubt. But I was just wondering if my paranoid ass got a lemon or if I'm just expecting too much out of an open top car.

 

Are we talking about the jackstands or the flimsy jacks that come with the car in the trunk? When I use the jack that came with the car and lift the car at the front jacking point (under the side sills), I don't recall the rear tire coming off the ground as well. The rear does go up obviously, but not to the point where the tire clears the ground. Are we talking about different jacks on different jacking points?

 

When I jack up the front high enough to change the front tire, no matter what jack I use the rear tire lifts off the ground about two inches if not more. If your car is not doing that then maybe there is something more to be looked into

 

Drive a 1990 Supra Targa and then compare them. My old targa felt like it was going to twist like a coke can when I hit a bump

 

Well, when I use that small jack on the side sill jacking point, I only lift the car just high enough for the front tire to clear the ground. I guess if I lifted it far enough, perhaps I could do what you did and the rear could clear the ground as well. Unless you jack it at the exact center of weight on either side of the car, the front and rear tires aren't going to lift the exact same amount even if you had an infinitely rigid chassis, since the other 3 springs (especially the rear one on the opposite side) are absorbing some of the weight. If the car had no suspension, then both tires lifting the same amount would prove a very rigid chassis. Again, I may be ignorant, so I could be talking out of my ass lol. Are you jacking more towards the middle of the car along the side sill?

 

Just out of curiosity... on those open top cars that have so much flex - wouldn't the frame loosen up over time and the car feel like garbage after some mileage? I can't imagine driving them and having fun.

 

How do you "feel the car flexing slightly"? I know you gave a detailed description in the OP, but could you nail down the symptom for us? The situation you describe, crossing expansion joint one wheel at a time, will give a noticable jump from bump steer alone.

 

As far as bending rigidity goes - the S2000 is largely unparalled. The backbone running through the center of the car ensure that the cars frame will not yield to bending. I would say that the S2000s bending rigidity SURPASSES that of many closed top vehicles.

As far as torsional rigidity goes - the S2000 is ON PAR with many current sports cars, and is probably surpassed by some newer ones. Although the heavily trussed X-bone frame migitates a lot of this twisting, this is a 9 year old car, and as someone mentioned chassis technology has come a LONG way. I would say that the S2000s torsional rigidity is easily on par with its open top competition and is probably only surpassed by the likes of Porsche 911s and such.

I'm not sure how accurate the figure of 57000Hz, but if it is anywhere close to this, then that would mean that the frame is UNBELIEVABLE stiff. Aston Martin quotes 27000Hz (approx.) for their CLOSED TOP Aluminum DB9 based off the VH architecture.

Honda saw room for improvement in the S2000's torsional rigidity and we see this in the upcoming S2000 CR which uses a brace to increase torsional rigidity.

 

I don't know where you got the 57,000HZ, but honda s2000 is 22,000 Nm/degee.

Only thing surpasses this rigidity for example:

ferrari Enzo, ferrari F50, Lambo Gallardo and not Murcielago, RX-8 (wtf), Mini cooper, Rolls Royce Phantom, VW Golf V GTI, VW Passat and only audi A8 in the entire audi lineup.

http://www.evolutionse.com/forums/showthre...ted=1#post52860

fourth post.