DJT

I'm still trying to get a feel for when / why this happens. But it seems as though under modest (all the way up to hard) cornering, my rear feels a bit unstable. The sensation is almost as if there were a large mass in the trunk (which is empty) that's shifting weight as I enter the turn. It creates a temporary sensation that the rear is going to hang out.

Another way to describe it would be if the cockpit where mounted somehow separately from the frame and the whole thing (cockpit) rotated about 1" when entering a turn, creating the sensation that the rear was about to hang, then stopped rotating and the car handled as I woudl expect.

I've taken a quick look under the car and don't see anything loose or missing. I'm running some cheap-o Riken wheels on stock AP1 16" rims.

D

ZDan

AP1's have that initial oversteer LURCH handling "feature". Most important thing: When you feel it, do NOT lift! Hang in there and as the car heels over handling becomes more neutral. If you lift or stab the brakes, she's very likely coming around.

Basically, AP1's have too much rear roll stiffness which gives initial oversteer, but then the rear bump steer (toe in with bump) sort of "catches" you. However, if you LIFT (or worse, stab the brakes) when you feel the initial oversteer, the outside rear toes OUT, *and* you've unloaded the rear tires, so a spin becomes a very real possibility.

Crap tires don't help, but even with the best tires this is sort of the nature of the AP1.

DJT

Wow. That's a bummer. Me no likey at all.

Would changing swaybars help? Would putting in a set of Bilstein coilvers help? PSS3s are the current "gold standard" correct?

I'd like to upgrade the suspension, wheels and tires anyhow. All the plastic in back of my head rattles (a lot) over railroads. I should do an amplitude / db test of exactly how load the suspension is over bumps.

Not Sure

Just keep driving it until you get used to it. It felt weird to me at first too but now that I expect it to happen it's part of the routine. And now I don't notice it nearly as much as when I first got it. Maybe because my driving technique has gotten smoother as a result.

olapua

This is the AP1 driving experience.

My AP1 handles the same way when I go autocrossing or on hard cornering when I brake/trailbrake. Like others have said just don't lift off throttle but feather on while correcting.

If you've previously driven mainly front-wheel drives then this will be a fun learning experience. If you're familiar with how rear-wheel drives handle, then maybe you should look at your tire pressure or alignment. Otherwise have fun and be safe out there.

cdelena

MY '00 and '01 are especially bad with a problem that was widely criticized and Honda fiddled with suspension tuning until finally getting it under control with the AP2.

Many of us have retuned the early suspension with changes to bars, springs, shocks, and tires. I finally have mine where I like it but would not want to do it again.

ZDan

Before I bought my '01, I had TONS of track experience in my modded '71 240Z (it's about 5 seconds a lap faster than the stock S!). The 240Z's Chapman struts maintain constant (or approximately so) toe with bump, and the car behaves VERY linearly and predictably, whether the setup is oversteery or understeery (and the setup has been tweaked continuously).

When I first tracked the S2k, even with literally thousands of track miles and over 12 years track experience, it spooked me a little. The handling is *initially* oversteery, but then settles in as the car rolls and the outside rear toes out.

It is astounding to me that the Japanese made the same mistake with at least three sports cars since the mid-80's: The FC RX-7, the NSX, and the S2000. All employed (at least initially) a rear suspension geometry arrangement where the rear toe changes with bump to give more outside rear toe-in during hard cornering.

This was a dumb idea from day one!

A litany of AP1's in the ditch/curb/oncoming traffic is the legacy...

They got it right with the 240Z 40 years ago!

ZDan

Initially they fiddled with spring and sway bar rates, but they only fixed the rear toe issue when they went to the AP2 in '04.

Why they hadn't already learned the lesson that you do NOT want rear toe to change with bump is beyond me...

zeroptzero

mine only gets that sensation if I shift midway through a curve or if I lift throttle, it isn't to the point of being unsafe but it does feel jittery. So two things not to do. The effect lessened recenty after switching to BF Goodrich tires from Yokohama S-Drives, which I think is attributable to the stiffer sidewalls on the Goodrich tires. I've got a set of Ap2 springs and shocks that I will run in the future, they stiffen the fronts and soften the rear which will decrease the effect somewhat.

Billman250

If the rear is toed out, it will be extremely drift prone.

Do the right thing, and get an alignment.