I wish Suspension would come back.

Anti-dive and anti-squat is (of course) nothing new. With wishbones, the amount of anti dive and anti squat is determind by the angle of the wishbones. Of course there are other ways to achieve anti-dive/squat, but that's the way I've seen used most often with wishbones. It affects weight transfer, and like anti-sway bars, it's possible to have too much of a good thing.

EXACTLY! Even though my AP1 isn't stock anymore, the handling isn't much different from what it was when the car was bone stock (because I like the stock handling), which is just GREAT for really tight autocross courses, but less suitable for faster courses and track days. Dealing with it on the faster courses is actually a part of the fun of the car, and is one of the reasons I prefer the AP1. In a perfect world I'd want the AP1 balance (or the balance I have now) on the PCA courses, and then something closer to AP2 balance on the faster courses at the SCCA events. I'm pretty sure the Gendron bar is going to give me that, and a little more (range of adjustment), but that remains to be seen.

Driving style makes a difference, but for me, the stock AP1 has too much oversteer bias for ideal corner exit from faster turns, while being almost perfect for tight autocrosses, especially when there are multiple pivot cones or long, tight, chicanes. I don't see how one is better than the other, because they're both better, depending on what you're doing with the car. It would have been nice if Honda had given us some adjustability in the suspension. We get that on sport bikes, so why not sports cars?

 

IMO, Even if the shaft diameter is increase without adding to the mass, there will still be "less twisting" due to the mechanical advantage. Kind of like a lever. But given a fixed thickness, the larger diameter will mean that there's more mass and material to twist, and this will also result in "less twisting".

Edit: Besides increasing the shafts ability to deliver torque, why would they increase the diameter? It doesn't save money or space.

BTW- I'm not a mechanical engineer, but I play one on the forums.

 

I use to say something similar at the start of some technical meetings.
"I don't actually know anyting at all, but today I'm pretending to be an expert on <fill in the blank>."


Check out this link for more poop on hollow and solid shafts.

 

This one is pretty interesting too.

 

OK Boys - heres some interesting info about the suspension and other stuff straight from Dan Carney's book...

IN-WHEEL SUSPENSION: With a solid platform established, the suspension is free to do its job unindered by interference from a felxible frame. The choice of suspension components is vast and the sleection is driven by many factors, such as performance, cost, and space required. Honda chose the design generally considered to be the best for high-performance handling, double wishbones. This layout is known alternatively as unequal length control arm. Both take their nakes from the different names for the suspension part that connects the wheels to the body. In this design it is called a control arm, an A-arm, or a wishbone. Both regardless of the name, its is the design used front and rear on all advanced race cars.
Like the frame, the suspension components themselves need to be rigid. "To increase the suspension's lateral rigidity, the rigidity of the body, the suspension mounting points, and the suspension itself was increased," Otobe said. "For the front suspension, the wheel center axle is located parallel to the lower arm input axle, to ensure efficient rigidity in response to input," he said. "For the rear suspension, the control is located in the lower front, and a wider span between the control arm and the lower arm fitting points was adopted for a considerable increase in rigidity."
A curious choice for a car that seeks light weight is the use of cast iron for the suspension of control arms. Virtually any other material would be lighter, but the cast-iron arms should probe durable and cost-effective.
The geometry of the rear suspension was tuned for antisquat characterisitcs, through the use of caster. Caster is angle between the steering axis and the vertical plane, as viewed from the side. It differs from camber, whih is the angle the wheel tilts from vertical, when viewed from ahead or behing. Anyway, the antisquat geometry discourages, as one would expect, the rear from squatting under acceleration, so drivers can pour the power on sooner when they are exiting turns. Honda calls its suspension an "In-Wheel" design, because none of the control arm components extend outside the diameter of the wheel. This makes for a very compact system, with only the coil spring and shock absorber extending higher than the tire and wheel. This permits a low hoodline, especially compared to MapPherson strut designs, as employed on the Porsche Boxter and the Toyota MR2-Spyder.
The S2000's shock absorbers are gas pressure units, and the rear suspension even boasts external reservoirs on its shocks. Like so many other components on the S2000, this is just like on race cars. The gas shocks help minimize body roll, which aids rapid weight transfer for neutral cornering and, like the antisquat geometry, puts the power to the road better. Because they suffer less damp body vibration from the body, theu contribute to the rigid feeling imparted by the chassis. The linear spring rates are appropriately stiff for a sports car withouit imparting a jarring ride.
Of course, while we are talking about limiting roll, we can't forget the antiroll, or antisway, bars. The S2000's "sway" bars measure 1.11 inches in the front and 1.07 inches in the back. These were tuned by engineers up until the S2000's public launch, as Honda sought to include maximum stability in its sports car. Journalists who attended the car's long-lead press launch in France reported that the preproduction prototypes they drobe at that time tended to oversteer, which can be fun in controllable amounts. But it can be scary and confidence-sapping on the race track in large amounts.

DRIVESHAFT, IFFERNTIAL, AND HALFSHAFTS: The driveshaft is equipped with constant-velocity joints at the ends, in place of the typical universal joints, because CV joints provide more consistent power transfer. At the rear end, a Torsen limited-slip differential provides maximum traction for the lightweight car. Its effectiveness is readilyl apparent when driving in the rai, a circumstance in which front-engine, rear-drive sports cars rarely excel.
Finally the power is transferred to the hubs through the half-shafts, which one could readily suppose are off-the-shelf items. But, as with the rest of the S2000m tge half-shafts were custom-designed after careful study. Under acceleration, a vehicle doesn't instantly launch into a smooth, linear acceleration curve. Instead, the acceleration oscillates briefly before settling down to a steady curve.
Of course, no driver can claim to feel that oscillation, but it turns out that the driver's perception of snappy acceleration depends on that oscillation being dampened quickly. iIf the drivetrain wobbles under acceleration, drivers will report sluggish acceleration, no matter what the stopwatch says. "Test results revealed that a driver feels acceration response as 'excellent; when the damping of acceleration Gs is rapid, that is, when the time to reach a steady G is short," said Otobe.
Honda's research into the problem found that 59 percent of the oscillation in the accleration curve is due to flimsy halfshafts. "We analyzed which factors contributed to realizing quick damping," he said. "We found the rigidity of the drivetrain, especially the torsional rigidity of the halfshaft, was the biggest contributing factor." So the S2000 has enlarged 36mm halfshafts to dampen oscillation as quickly as possible, so drivers feel that the S2000 is as quick as the stopwatch says it is.

 

Good stuff.

One question. I thought caster was what gives us self centering steering. Does angling the A-arms for anti-dive/anti-squat also change the caster, or is there some way to achieve anti-dive/squat using caster? I'm confused, because I thought they were two different (or actually three different) things.