Heck, I totally forgot to respond to the question about the half shafts. According to Honda (I can't give you a link or anything, so you'll just have to take my word on my source) the half shafts in the S2000 are something like 50% larger in diameter than they'd normally use in a car with the S2000's power, and the reason is supposed to be because it makes the car's acceleration subjectively faster. There are others here who can verify that this actually came from Honda, and the idea seems to make sense. Why else make the half shafts stronger than necessary?

 

It seems to me that making the half shafts larger would achieve a couple of things:

1) Slower Acceleration (more inertia)
2) Quicker Deceleration in neutral (ie no brakes, no gas) (more inertia)
3) Higher Weight
4) Higher Strength and rigidity
5) Ability to break traction on the rear is (I do not know to what degree) determined by the rigidity, weight, and diameter of the half shafts.
More rigid (heavier, larger diameter) means that you waste less power twisting the half shafts, but more inertia (heavier, larger diameter) means that you waste more energy spinning them.

 

IMO, the larger diameter in the shafts (assuming they are hollow) permit a higher torque capacity while using a thinner wall. Also, regarding the polar moment of inertia, the use of less material farther from the rotational axis obviates any loss of acceleration. Furthermore, the relatively small radius of the shafts, even keeping the wall's thickness intact, would render any disadvantage negligible.

 

Going back to the original post, I have to agree that the S2K supension is fairly conventional. In fact, the changes done for the AP2, are a textbook example of how to reduce oversteer.

 

What do you mean by subjectively faster?

 

With thicker shafts, there's less torque lost. The driveshaft twists a little tiny bit under acceleration. This limits the amount of torque that reaches the wheel. The thicker and shorter the drive-shaft, the less it twists. I don't know that the difference is enough to notice, but maybe honda does.

As an example, did you ever take a close look at the socket most tire shops use to put lug nuts on? It long and thin. This allows a specific amount of torque to reach the lug before it starts to twist. Same basic idea.

 

^^ Exactly.

 

I agree, but we're still at the mercy of Honda for an explination, and their explination seems to be reasonable.

 

That's what I believe too, except that I think some of the changes were aimed at other issues (in whole or in part) in addition to reducing oversteer.

Part of my problem(s) come from the fact that I've done almost all my automotive work on my own, so I've learned from books, but have rarely had anyone around looking over my shoulder to make sure I was doing things correctly (due to some defects in my understanding). I hope Suspension responds, but I'll be satisfied if nobody manages to expose any water mysteries that I've overlooked.
LOL, for that matter, I'll be equally satifsied if we uncover any holes in my understanding.)

 

Actually, you'd have to ask Honda. It's their words, not mine.

I think I know what they mean, but I'm only guessing, based on the kind of change they're talking about and what they said. A common example of a car being "subjectively faster" is the way most people will think a car is faster after a louder exhaust system is installed. It may "feel" faster only because it's louder, but the subjective impression can be real enough to be enjoyable.