The other day I was coming off the highway and took a 180 degree offramp fairly fast. I wasn't anywhere near the tractive limit of the tires while cornering, but all of a sudden it felt as if the car was starting to experience a dangerous amount of oversteer. It felt as if the back end was sliding out, but the tires were completely planted and quiet. I also gave no input through the wheel to induce this so it was kind of scary. I was wondering if anybody else has experienced this in their RX-8 and has any idea what causes it. I'm wondering if it's some type of corrective feature built into the car, but it always scares me when it happens. My last car was a 3rd gen rx-7 which I alway drove on winding roads fairly fast, but I've never experienced this before. I've experienced many instanced of actualy oversteer in both the rx-8 and rx-7, but this is different. The best way I can explain it would be to take the real feeling of over steer, but you can't hear it and you can't feel the wheel movement of the front tires through the steering wheel like you normally can. I am the only one?


I should also note that on this specific off ramp which this has happened on, the road has a slight dip close to the apex of the turn. It's nothing major, but definately noticable and part of the reason that I don't take the turn at higher speeds. But evn so, I still feel this "ghost" oversteer for about a second or two. Also this is with the DSC and everything enabled.

 

Body Roll maybe?

 

Yes, you will feel a little body roll, and if you push the car faster it will begin to slide sideways in an even fashion. Not the rear end moving out, but all four tires.

 

With DSC on or off?

 

Might wanna upgrade to stiffer mazdaspeed springs/shocks to eliminate this, and some bigger chassis braces.

I like Autoexe cause they are very sturdy, but add lots of weight compared to other carbon fiber/metal tubes.

http://www.specr.com.sg/rx8autoexe.html

 

You can't have oversteer with the "tires firmly planted". You detect deviation from a "coordinated turn" via sense of sight, touch, and sense of balance (inner ear). Also, tire squeal but you say there wasn't any. Your brain is also comparing this feedback to what it is expecting to recieve based on experience and the inputs you're giving the car.

Somehow you had a situation where these senses did not agree with each other. Possibly the dip is related to this. It's also possible the active traction and stability systems of the car were activated, meaning you were closer to the limits than you thought. The dip could be playing a role here too by unloading the wheels, possibly reducing traction to the point where DCS/TCS is activated.

 

My experiance with cornering is fun, the rx8 is foregiving, it feels like the *** is coming out but you can push it, but you have to be carefull and know what your doing, know your limits, go practice on an open roadcourse. Drive safe.

 

forget it......

 

onramp = slippery by nature. oil, grease, rubber on the road from higher than average traffic. This is my experience anyway.

 

One time , I caught up to a truck on an on-ramp that was spilling gas - no gas cap. Other times, I've seen trucks spilling water. If you hit the line where they are dripping, you can lose traction. Also, sometimes there is a surface change. One on-ramp that I use regularly goes from tarmac to concrete, and the concrete is more slippery.

 

My guess is that:

1) The "dip" changed the weight distribution of the car momentarily enough to induce some oversteer rotation that caused your "butt-o-meter" to flash a warning

OR

2) There was some sort of slick substance on the pavement there. Either way, not terribly surprising.

 

Camber of the road caused it, definitely. You were going too slow. Give it more gas to lighten up the front end!

 

Yeah... there's a nice S-curve on the south end of my city where, halfway through the 2nd curve, there's a very pronounced dip/rise in the road. Scared me sensless the first time I went over it... You might also be experiencing a change in the rate of descent. Maybe the dirt beneath that section of road settled a bit more than higher up, giving you a different sensation.

And finally, I've yet to actually hear my tires. They're very quiet, even during the couple of hard launches I've done. If you ever get that feeling that you're about to start facing the other direction, just give the car a small bit more gas. Sounds counter-intuitive, but it's actually the only real solution (unless you can suddenly straighten out). It will force more weight onto the rear end and help you regain control.