ABS -vs- non ABS Vipers

[Cobraken]

Years ago I took a high performance driving class @ Bondurant. With cars that had the ability to turn off the ABS we went into a corner @ speed braking hard. First w/out the ABS & then with the ABS. There was a huge difference in steering the car while braking. The rest of the day we practiced braking w/out the ABS trying our best to emulate the ABS control. I notice that while watching the Speed World races on TV the commentators make a big deal out of the advantages of ABS especially in the heavier (Viper) cars. I also remember the magazine tests of the early Vipers & the writers were very critical of the Viper not having ABS being sure the cars would stop faster with it. Later articles have been more favorable since ABS was introduced.

Bottom line: Cars stop faster & with better control with ABS. Will it save you in every situation? No way Jose. I understand the argument that the Viper was designed to be a low tech in your face kind of car. I understand the challenge of controlling the beast. But I believe that arguing that ABS is not an advantage is ignoring the truth in some sort of my car & ability are better than yours braggadicio logic rather than admitting ABS provides a braking advantage.

Drive what you want for the joys that it gives you.

 

[wigginz]

Don't mean to hijack the thread, but it could provide a good visual for making the decision. Would the Viper at the end of this clip have made the turn with ABS? Or at least given him a chance? http://youtube.com/watch?v=ySLvePpB1vw

 

[Tom F&L GoR]

ViperJon beat me to it, but if ABS was such an aid, then AX events should be dominated by ABS cars. So far, they aren't. Or maybe the NJ version of ABS doesn't work...

There are some advantages (steering/braking and also uneven surfaces) but perhaps having it or not is a learned driving style rather than a benefit.

I have ABS on my '06 Charger and can threshold brake at a more rapid rate until ABS kicks in- then the chattering slows me down more slowly. No, I can't do it every time at all, but it shows to me that ABS broadens the braking performance, but it doesn't automatically improve it.

 

[GR8_ASP]

Ah, but here is the rub Tom. That is if that Charger was not equipped with ABS threshold braking would be far inferior to what you now experienced. That is because rear brake bias would drop so much to avoid rear lock-up in all possible situations. So you benefitted from the inclusion of ABS.

As to ABS being superior your evaluation is not a true test. A race quality 4 channel ABS system is superior to the best Formula 1 drivers. And makes them all near equal. That was why they banned it in Formula 1. Your car has a modest 3 channel system with resulting strong feedback. It cannot compare to state of the art.

 

[GR8_ASP]

Ah, but here is the rub Tom. That is if that Charger was not equipped with ABS threshold braking would be far inferior to what you now experienced. That is because rear brake bias would drop so much to avoid rear lock-up in all possible situations. So you benefitted from the inclusion of ABS.

As to ABS being superior your evaluation is not a true test. A race quality 4 channel ABS system is superior to the best Formula 1 drivers. And makes them all near equal. That was why they banned it in Formula 1. Your car has a modest 3 channel system with resulting strong feedback. It cannot compare to state of the art.

 

[Chuck 98 RT/10]

Gen I and early Gen II is about 125 to 130 ft. Gen II ABS about 110 ft.

You didn't provide a link but even so, the early GenII were on 17-inch rubber and who knows what kind of pads. The best way to compare is to eliminate all variables and isolate the actual ABS feature. The biggest factors would be to use the same exact wheels, pads and rotors as well as suspension, suspension settings and finally scale the two cars to keep them at the same weight. Dunno if there were any other system differences between them.

 

[GR8_ASP]

Chuck that leads into exactly what I am saying. If you have a non ABS system set up exactly the same it will be prone to early rear lock-up. That is a situation an OEM must avoid. So to avoid early rear lock-up the rear piston size or pad size or master cylinder rates will be reduced to make the rears much less effective.

They must be set up so in the worst conditions (high speed wet, snow, etc) the fronts lock first. That is the safer condition for as you know rear lock-up results is more instability than front. A proportioning valve is used to help but unfortunately the standard proportioning valve is incapable of adjusting for differing conditions and works only under high system pressures. Good ABS systems include electronic proportioning to allow the rears to do much more work (kind of like the kits from Tom or Stop Tech).

So the bottom line is for an OEM system you will never get a non ABS system to be equivalent or nearly as capable. The best would be a defeatable ABS system but I fear the lawyer/government would not allow that. Possibly on an extreme performance car you could have a race setting that desensitizes the system such that it is not invoked, even under race conditions.

 

[CANTDRIVE55]

"The best would be a defeatable ABS system but I fear the lawyer/government would not allow that. Possibly on an extreme performance car you could have a race setting that desensitizes the system such that it is not invoked, even under race conditions."

BUT...they allow a defeatable passenger airbag in a two-seater for child safety (Even though you shouldn't put a child in the front seat of a vehicle). I guess they have to "feed" the lawyers something.

 

[Chuck 98 RT/10]

They must be set up so in the worst conditions (high speed wet, snow, etc) the fronts lock first. That is the safer condition for as you know rear lock-up results is more instability than front. A proportioning valve is used to help but unfortunately the standard proportioning valve is incapable of adjusting for differing conditions and works only under high system pressures. Good ABS systems include electronic proportioning to allow the rears to do much more work (kind of like the kits from Tom or Stop Tech).

Tech topics always end up in a performance discussion. But that isn't the point the non-ABS crowd is trying to make.

If all a guy wants to do is go fast, then hop up a Z06 and let it do the driving for you.

But if a guy wants to learn how to go fast, buy a Viper...preferrably pre-ABS.

 

[Tom F&L GoR]

Ah, but here is the rub Tom. That is if that Charger was not equipped with ABS threshold braking would be far inferior to what you now experienced. That is because rear brake bias would drop so much to avoid rear lock-up in all possible situations. So you benefitted from the inclusion of ABS.

As to ABS being superior your evaluation is not a true test. A race quality 4 channel ABS system is superior to the best Formula 1 drivers. And makes them all near equal. That was why they banned it in Formula 1. Your car has a modest 3 channel system with resulting strong feedback. It cannot compare to state of the art.

Well, if I benefitted from larger rear brakes, I agree. I think it still says a balanced system is pretty good, ABS or not. And I wouldn't hand the credit to ABS just yet.

Even so, I tend to not agree with you at first because if OEM ABS fails, then the mechanical/hydraulic system that remains is "dangerous." I don't think that would be allowed, so perhaps the rears aren't as oversized on an ABS car?

Anyway, I still won the AX with a Gen 1. Second place NY car was also non-ABS. Let's see who else goes to Detroit and what they drive. That would be an interesting survey.

 

[PatentLaw]

Respectfully, this has been talked about before. As for people saying that there is no proof or tests that show that ABS cars are better than non-ABS cars, I present the following article:

http://www.edmunds.com/insideline/do/Drives/Followup/articleId=48641

Again, posted before. Those who choose not to believe, well then be my guest. The weight of the evidence is not on your side. As for winning an autocross, congratulations. Maybe you would have done even better in an ABS car. We will never know. Perhaps it is the driver and his capabilities that far surpassed the competition. A potentially inferior car beating technically superior cars. A feather in your cap showing your skill.

 

[GR8_ASP]

Tom, I do not think they protect for btake bias with full ABS failure. When that happens the ABS light is illuminated.

My experience on the track with stock SRT brakes is such that when my ABS failed (due to a sensor failure) my right rear locked up first. Caused a rotation at 130 mph that I do not want to repeat. Since then I found the trick is to increase the front brake friction coefficient by using Brakeman 3's with stock rear brakes. That way the bias is slightly more front than stock and eliminates the rear lock-up.

As to autocross I would expect braking is not so much a part of your dominance. Other aspects must be superior . Road racing is more sensitive to brake potential in my humble opinion.

 

[luc]

"They must be set up so in the worst conditions (high speed wet, snow, etc) the fronts lock first. That is the safer condition for as you know rear lock-up results is more instability than front."

Not sure where you got this idea from, it is a lot safer/easier to control a rear lock-up than a front one for the simple reason that you loose all steering with a front wheels lock-up.
As for the rear brakes being less "effective" than the fronts,it's simply due the fact that during braking weight is transfered to the front and consequently more traction is available in front that at the rear,so, obviously you want less "braking power" at the rear.

Furthermore, in a worst case scenario, if stopping distance is paramount you want the rear to lock, not the fronts for the simple reason than a locked-up tire don't stop you nearly as good and most of the braking is done by the fronts.

 

[luc]

it'a a silly argument, obviously an ABS system is almost always better than a non ABS system ( I said "almost" because there are 2 situations were you will stop faster with a locked wheel, snow and sand.the locked tire will dig in and push a ridge of snow/sand in front and that will help you slow down)

As Chuck said, the question is not what is better ,but if you want the car to drive you/be in control (ABS,Traction control,etc) or do you want to be the one driving the car/being in control.

One thing is sure,I have been racing for a long,long time, from Formula V to Vintage Big Bore, to a Roush T/A and the skills that I have learned make me a much better and safer driver on the road with a non ABS car than without those skills and a ABS car.

One more thing, it has been my experience ( I run a open-track/race club in CA) that 99% of new drivers with ABS cars have developped (spel) very bad braking habits ( as going fast in with the ABS fully on and slow out instead of slow in and fast out) and we have to spend a lot of time teaching them the basis of braking and weight transfer
We do not have quite the same issue with the few drivers of non ABS cars

 

[GTS Dean]

Hi folks - late to the party but wanted to get my 2 cents in.I owned an SRT for a while and the brakes were phenomenal. ABS was part of the equation, along with bigger rotors, better system hydraulic balance and different anti-dive geometry.My 93 had terrible brakes - mostly due to a crappy booster design and geometry second.The Gen2 has revised geometry, less unsprung weight and *much* improved booster modulation. It suffers from the same poor component balance of the Gen1. Spending $900 on rotors and rear caliper upgrades makes a *huge* improvement to performance. The OEM 18's are horribly heavy and negatively affect handling. I've never driven an ABS Gen2, but I'm solidly with Chuck in this performance debate.IMO, the best factory improvement to the GTS was the inside hatch release and power mirrors. I wouldn't value the ABS more than $500 over an equivalent standard model. Get your favorite color and drive that sucker.

 

[Chuck 98 RT/10]

As for people saying that there is no proof or tests that show that ABS cars are better than non-ABS cars, I present the following article:

http://www.edmunds.com/insideline/do/Drives/Followup/articleId=48641

Now, that figure gets shaved by 40 feet to 115,

Thanks for the link. After five years it is the first I had seen any comparison. But the question remains, what are the differences between the two systems besides the ABS tech? Dunno myself, just askin'.

 

[VENOMAHOLIC]

Tom, I do not think they protect for btake bias with full ABS failure. When that happens the ABS light is illuminated.

My experience on the track with stock SRT brakes is such that when my ABS failed (due to a sensor failure) my right rear locked up first. Caused a rotation at 130 mph that I do not want to repeat. Since then I found the trick is to increase the front brake friction coefficient by using Brakeman 3's with stock rear brakes. That way the bias is slightly more front than stock and eliminates the rear lock-up.

As to autocross I would expect braking is not so much a part of your dominance. Other aspects must be superior . Road racing is more sensitive to brake potential in my humble opinion.

------------------------------------------------------------------------------------------------------

ABS sensors and ABS in genseral fails more often than you realize. I am not a racer (yet) but I drive an oversize truck 50hrs+/week with ABS. The sensor failed and I recognized it right away but a rookie driver might have rear ended somebody hard in the same situation. It also has failed on my S-10 Blazer. BTW, ABS ***** on snow and ice. I would gladly rather manually pump the brakes than lose control of vurtually everything when the ABS goes off.

Trucks and cars have to withstand years of torture from the elements. There is no way of inspecting all the extra electronic crap on our vehicles other than to see if nothing is hanging when on a lift. Sensors fail suddenly either when jarred from a bump, shorted, or damaged by a mechanic while working on something else. I specifically wanted a 00 RT/10 to avoid ABS on my Viper but unfortunatly, it is almost impossible to gat a new car without it now.

 

[Tom F&L GoR]

>Maybe you would have done even better in an ABS car.<

Part of a previous AX (the old rendezvouz tours) was a ride in an SRT. I was worse. I do think for dry tracks, no distractions, that a setup non-ABS car is very capable. In the rain, when the deer jumps in front of your Gen 2 with crummy rear calipers, you'll eat venison. And AX has the same or greater proportion of braking as a road course - unfortunately due to the tigher quarters it's even harder than a road course to remember to brake in a straight line, too. Makes for a good lesson in braking. I'm still surprised that the legalities allow the ABS to fail and have a rear bias...

>Not sure where you got this idea from, it is a lot safer/easier to control a rear lock-up than a front one for the simple reason that you loose all steering with a front wheels lock-up.<

luc, all the occupant protection systems are designed for frontal collisions - seat belts, air bags, crumple zones, etc. The OEMs want you to hit head-on, and by law, the braking system makes you do so. Therefore, whether you like it or not, it is safer to loose steering control and slide forwards than it is to lose yaw control and hit the tree sideways.

The only time I ever hit something was when the rears skidded and the quick bobble got me in the grass (and the guardrail.) Personally I would still prefer front locking first.

This kind of discussion always makes me wonder how to organize a brake-off.

 

[GR8_ASP]

Good comments Tom. As to my road vs autocross comment it was not aimed at the amount of braking, but at the speed at which the brakes are engaged. Road track it is generally in the 80-130 mph range when first applied to a turn in speed of around 50. Autocross is normally with braking starting at much lower speeds, say 50 to 60. Since brake energy requirements are related to the square of the rotational speed of the wheels and vehicle the braking situations are far different.

 

[Tom F&L GoR]

Agreed, it can be different. I think perhaps in AX I do have an advantage. By learning to slightly angle the car upon brake application I can begin to rotate it and continue rotating it with throttle. If I don't start the rotation with the brakes, I can't smoothly finish with throttle - it becomes messy and I lose momentum. I couldn't do this in an ABS car; or I would have to learn to drive differently. Perhaps this comment goes to Chuck's thinking that driving is "becoming one" with your car when you do so, you can go quickly, safely, and comfortably.

 

[Tom F&L GoR]

Duh, trail braking. Beat every to it.

So, can you trail brake with an ABS car?

 

[C O D Y]

When a kid jumps out in front of you....... NO. ABS is your best bet.

Duh, trail braking. Beat every to it.

So, can you trail brake with an ABS car?

 

[REDSLED]

Duh, trail braking. Beat every to it.

So, can you trail brake with an ABS car?

Yes you can. Trail braking has nothing to do with ABS. Trail braking has to do with engaging the brakes and accelerator at the same time so as to minimize weight transfer in a turn.

 

[Tom F&L GoR]

That's a different definition than I've previously seen. I usually read that braking in a turn increases the weight transfer so as to give the fronts more vertical load and therefore more traction for turn-in.

In my case, whatever it is I do, it decreases rear traction (which is why I asked about the ABS involvement) and helps slide it around the turns better.

 

[REDSLED]

I may be referring to "Trail Braking" as "Left Foot Braking" My mistake as I usually use the left foot to brake in tight, slower turns to help me get through faster.
All I know is that I want to keep the back end planted so that I can keep the power down, while at the same time slowing down enough to be able to make the turn. Once you brake, you are loading the front tires, it's the back end that will tend to get light. I might be expaining it wrong, but that is my perception of what I want to accomplish. Having the back end light in a Viper while racing isn't fun and makes for slow progression.

 

[Tom F&L GoR]

If anyone gets this far in the thread, they'll see the road race vs. AX difference. I want a lighter end to rotate around cones, you want a planted rear to get out of turns. I think it represents more of how to get better times; road race requires more straightaway speed than AX (all turns.) Cool how one can learn to use the hardware to get what you want.

 

[REDSLED]

Exactly Tom. Good thread.

 

[carguy07]

http://www.thetruthaboutcars.com/?p=2006

 

[C O D Y]

This quote is great.....

"The taxi study proved that drivers tend to take greater risks in cars equipped with ABS "

Now can you find a study for Chuck's speed bump problem?

http://www.thetruthaboutcars.com/?p=2006

 

[Tom F&L GoR]

I also have read that in a panic stop, people tend to **** the wheel to avoid the problem. Without ABS they plow into the object, but the occupant protection system is designed around a frontal impact, so survival rates are good.

With ABS, jerking the wheel executes a turn, and apparently sometimes a rollover. In either case, the turn veers into oncoming traffic on the left or a tree on the right, perhaps with a side impact. So yes, I can see not more, but more serious accidents with ABS equipped cars. This was anectodally the case with fleets that Texaco used to use in lubricant tests.

Obviously we need ABS to be assisted by LCC (Lane Change Control), APF (Auto Parking Feature), GPS (Global Positioning System), the speedometer, ESP (Electronic Stability Control), and for Chuck, SBA (Speed Bump Avoidance.) Its the only way I can see ABS being fully safe in a quick reaction, life threatening event.