Close Call, NSX will snap spin unpredictably

[liftshard]

......i'm getting tired of this abs argument
why don't we just test two nsx one with abs on and one off and see which has shorter stopping distance.......then we have an anwser!!!

Can we put a couple patches of sand or gravel in the braking zone?

My point is about real-world performance, not test track performance. ABS is far more accomodating of traction changes than standard braking systems. And this is exactly why it TYPICALLY permits the shortest stopping distances.

C'mon, we've ALL braked hard at some point and got into the ABS and then had it go back off on us. Had we not had ABS, we'd have had to have pumped or released to hook the tires back up. We've also all probably slid furniture, fridges, and other heavy things across surfaces of varying coefficients of friction and noticed that the things seemed to require less force to keep moving than they did to GET moving. This is because the coefficient of sliding friction is always less than that of static friction. Often, significantly less, especially when you start adding melting rubber into the equation.

 

[ATERPAK]

I didn't B.S. about driver aids being for the birds. I use it with great advantage in my A4 all-wheel drive Avant wagon when cornering. So please no flames. But I've been around, or behind too many people who have the best that money can buy for a car and still can't avoid either an accident or control a car in an emergency situation. Proper driver training makes you aware of your car's full potential, driver aids and all, and how to use them to stay alive out there in the real world. It also teaches you about the laws of physics which concern your car and hopefully avoid going beyond those laws where even the best driver aids can not handle.

 

[NsSeX]

I don't know if this is relevent to the current topic or not, but from my recent trip down to california, I found my self in a situtation where I had to slam on my brakes due to an oblivious driver cutting me off. I hit my brakes and broke loose my tires, after coming to a complete stop I realized that my abs hadn't kicked in. Can someone explain that for me?

Also on my M3, I have DSC (Dynamic Stability Control) and i've found under hard driving the car is much more easier to handle and correct with it turned off rather than being turned on. With the DSC turned on, i've found it to be more of a annoyonce than help.

 

[ATERPAK]

There could be a number of factors affecting when the ABS comes in. If you changed your tire brand, they may break loose a little quicker than what the ABS could sense in a timely fashion. Changing the brake pad type may cause a delay. I remember this happening to me when I had to do a panic stop to avoid hitting a car in front of me and I just kept sliding toward the car and finally the ABS started working and allowed the car to steer away to just clear the car. Scared me sh..less. I have no answer as to why it took so long for it to work but the early ABS system on the NSX is good but not as good as the new systems now on the market.

 

[nsxtasy]

I hit my brakes and broke loose my tires, after coming to a complete stop I realized that my abs hadn't kicked in. Can someone explain that for me?

I would guess that it's one of two things: either you didn't really break loose your tires, or there is a problem with your ABS. My suggestion is that you test your ABS. Go to an empty parking lot or an empty road in the country, make sure no one is around you, accelerate to 50-60 mph, and slam on the brakes as hard as you can. If you feel pulsing in the brake pedal, ABS is working. If not, have it serviced.

Incidentally, there are times when I've tried this without feeling any pulsing, but I realized that I just wasn't slamming on the brakes as hard as I could, even though I thought I was. It can take a lot of effort to make the wheels/tires lock up, a lot more than you think. Which is why it's also possible that you thought the tires had broken loose, when maybe they hadn't. Regardless, you need to test it out and see if ABS is working. (Actually, it's a good idea to do this at least once a month anyway, to keep the ABS solenoids from sticking.)

 

[liftshard]

I would guess that it's one of two things: either you didn't really break loose your tires, or there is a problem with your ABS. My suggestion is that you test your ABS. Go to an empty parking lot or an empty road in the country, make sure no one is around you, accelerate to 50-60 mph, and slam on the brakes as hard as you can. If you feel pulsing in the brake pedal, ABS is working. If not, have it serviced.

Incidentally, there are times when I've tried this without feeling any pulsing, but I realized that I just wasn't slamming on the brakes as hard as I could, even though I thought I was. It can take a lot of effort to make the wheels/tires lock up, a lot more than you think. Which is why it's also possible that you thought the tires had broken loose, when maybe they hadn't. Regardless, you need to test it out and see if ABS is working. (Actually, it's a good idea to do this at least once a month anyway, to keep the ABS solenoids from sticking.)

It's also possible that the ABS system only monitors like the FL and RR tires or something and it was only one of them that broke loose. I had to slam on brakes the other night and ABS came on, some jackass in a Cherokee with no goddamned brake lights. The road was wet, and I just steered around him. In the dry, however, it's a lot harder to lock the wheels up and the ABS system may not be set to activate on a one-wheel lock or something.

 

[NsSeX]

Thanks, I'll definetly go and check my brakes once more.

 

[NsSeX]

I would guess that it's one of two things: either you didn't really break loose your tires, or there is a problem with your ABS. My suggestion is that you test your ABS. Go to an empty parking lot or an empty road in the country, make sure no one is around you, accelerate to 50-60 mph, and slam on the brakes as hard as you can. If you feel pulsing in the brake pedal, ABS is working. If not, have it serviced.

Incidentally, there are times when I've tried this without feeling any pulsing, but I realized that I just wasn't slamming on the brakes as hard as I could, even though I thought I was. It can take a lot of effort to make the wheels/tires lock up, a lot more than you think. Which is why it's also possible that you thought the tires had broken loose, when maybe they hadn't. Regardless, you need to test it out and see if ABS is working. (Actually, it's a good idea to do this at least once a month anyway, to keep the ABS solenoids from sticking.)

Well actually thinking about it, I did hear the tires screech for a second of two. So i'm quite sure the wheels broke loose/locked up. I have felt the abs pulsing in other instances though....

 

[ncdogdoc]

My first thought is change of wheel sizes.

Second is a problem with the ABS system.

The NSX uses four separate wheel speed sensors that utilize magnetic pulses from the hubs to detect motion, so it should pick up even the shortest amount of time that any wheel stops turning.

 

[nsxtasy]

My first thought is change of wheel sizes.

I assume you mean tire sizes, rather than wheel sizes, but... I thought the ABS detects and activates on wheel spin regardless of the tire sizes. Unlike TCS, which can be activated (and think that there is wheel spin) simply as a result of different tire sizes, even in the absence of actual wheel spin. No?

 

[RON98]

i think it is driver error. You could have saved it.

 

[Patdeisa]

I'm sorry, but that comment can't be further from the truth. FWD with neutral balance? Unless it is properly setup race car, all the FWD cars out there are understeering pig! The manufacturer intentionally made those FWD family car an understeering pig because most people, like you, don't know how to drive well. Understeering is the safe way to cover their ass. When people go into the corner and went in too fast, for understeering car, it is easy to gain it back by lifting the throttle or hit the brake. If it is a neutral car, this kind of behaviour will spin you around.

I disagree with this comment on all FWD cars being understeering pigs. I autocross my RSX-S in the stock category (only differences from OEM are tires and tire pressure*). I have twice experienced lift throttle oversteer at 50-60 mph- once I saved by having room to counter-steer, add a little gas, and settle the car, however the second time the car spun 180°. Neither times were the brakes used that created the oversteer (however, brakes were used once I knew I was going to spin- both feet!). It does have understeer at slower speeds, but above 40 mph, it has a tendency to oversteer more. As stated above, a more neutral car will spin when throttle is lifted. For reference, other stock and modified owners have spun their cars in similar circumstances (at a track or autocross), so I'm not the only one. *(Tire pressure was +5 front and +7 rear from normal driving).

However, it is true that a lot of FWD cars that have terrible understeer (my only experience in another FWD is a '89 Integra which does). Even my '91 AWD Eclipse understeered terribly. There are a few, however, that are a lot more balanced than expected.

 

[WingZ]

I'm curious as to how NSX owners who previously had S2000's think the car handles. I had two S2000's and the NSX's tail swing is waaaaay more predictible than my first S2K. I can actually turn of the TCS and get it to step out whenever I want. Coming from the S2K the NSX is so stable and predictable it's hard not to push it because it's limits are so high!

 

[Morrie]

Matt,

It's perhaps presumptuous of me to comment here because I have maybe ten miles in an NSX so far, but I have about two decades of instructing, mostly in Porsches.

I agree with what Dave Hardy wrote and would add that if you don't catch the first step out quickly, you are dog meat. If the initial spin becomes inevitable, (and you will almost always know that) or if you overcorrect and it comes back the other way, we teach the Mark Donohue "Both feet in" technique. Your best chance of stopping without a collision is to lock up the brakes, get the clutch in and hope for the best.

I understand that NSXs are tire eaters because they were set up for maximum track performance. I'm told that some people dial the aggresssive alignment out of them to preserve tire wear, thus making them more slippery.

I'd be interested in comments by people who know about this.