ABS Delete Any one runs without ABS

[Lance Racing]

Our E30 PRO-3 series started with ABS on the cars back in 2003, and we changed the rules in 2006 so now all the cars 40+ run without ABS. We did it for 2 reasons.

The early E30 ABS system exhibited "lock up" sometimes, giving you no brakes going into a turn. Results: massive crash.

We also felt that learning threshold braking was part of good driver development. As our series is a driver development series, having everyone not have to rely on ABS we felt was a good thing.

As a group we flat spot very few tires. Personally I've only flatspotted 1 tire in 7 years of racing.

For general driving on the street, you should keep the ABS.

[dreeves]

Our E30 PRO-3 series started with ABS on the cars back in 2003, and we changed the rules in 2006 so now all the cars 40+ run without ABS. We did it for 2 reasons.

The early E30 ABS system exhibited "lock up" sometimes, giving you no brakes going into a turn. Results: massive crash.

It's interesting, Lance -- my E30 M3 still has ABS. Out of all the corners on the 10+ tracks I've learned, there's only one where I really wished I didn't have it: turn 2 at Pacific Raceways. The pavement changes there are so dramatic that with a stiffly-sprung car, you really have to time your braking around them. Get it wrong and the car gets light, the computer thinks you have no traction and won't give you any brakes. It's a problem.

In general, I do prefer having ABS on the track; mostly as a failsafe. Because you can always beat it with good threshold braking, I think of it like a little bit of haptic feedback that you've gone over the limit.

[e304me]

Can you guys even tell that your abs is working? On some cars you can really feel the pedal pulsing but on my car It just feels like the pedal has reached a stop

[dreeves]

Can you guys even tell that your abs is working? On some cars you can really feel the pedal pulsing but on my car It just feels like the pedal has reached a stop

absolutely. sounds like there might be something wrong with your braking system.

[Wh33lhop]

Yes, especially on older cars with ABS you will feel the pedal pulsing when ABS is activated.

[RangerGress]

My ABS didn't work for a couple months a couple yrs ago. I initiallly didn't think that it was any big deal...figuring that I'd be able to detect the onset of lockup. But what I found is that with the rapidly changing track surface and car balance, I could not always detect the onset of lockup. Sometimes I didn't identity it until a tire was clearly locked up and skidding.

After I flatspotted 3 tires I got more serious about fixing it. New relay and a replacement of the brake warning light in the dash fixed it.

[mightywhitey]

Question here

I have deleted the abs system and am wondering what is the best way to remove the wiring for it.. I have the wires seperated from the harness and wonder if cutting and capping the wires and just tucking them under the fuse box is the way to go or should I remove the wires from the fuse box entirly. Is there any benifit other then the obvious risk of fire if I leave them IE no check faults? Thanks

[Fair!]

ABS is one of the few "Driver aids" that have been forced onto modern cars THAT REALLY WORKS. Real racers use ABS is the system is even halfway decent. They banned ABS in F1 because it was making the cars faster. Just like they banned full auto shifting and some of the other driver aids - because they worked. They don't ban something in F1 because it makes the cars slower.

For autocross using ABS regularly makes a night and day difference. I drive deep into a corner abusing the crap out of the brakes, and I dip a BMW into ABS mode often. Left Foot Braking should always be used in Solo, and anyone who says otherwise has never done real testing. Its several tenths on a 60 second course, up to a half second. And having the ability to dip into ABS makes all the difference when you are a LFB whore. According to data logging and comparison with my co-drivers, braking into ABS with a BMW works. Whenever I gain time on my less berserk braking co-drivers it is always under braking.

There is also a confidence factor that cannot be ignored. When you risk flat spotting a tire you will always brake just a little bit less than the car can get to. You avoid threshold braking. Sure, on a road course you usually don't want to be in the ABS on every lap or you will overheat the brakes. But when you need to make a pass? Oh hell yes I will. And in Time Trial, or qualifying, when one lap matters, using ABS can drop a tenth or two here and there.

And some BMWs don't have the best brake balance without ABS. Our E36 LS1 car for instance - without ABS it couldn't stop worth a damn. This car has E36 M3 brakes front and rear, 2500 pounds, giant R compounds (275F/315R) with a full '95 M3 ABS system in place. It would easily pull 1.1-1.2g under braking, with working ABS mode. We took it to the SCCA Solo Nationals in 2008 and it was working great, going fast as hell in practice. Then 3 days later, on my first competition run, the ABS failed. The front tires locked horribly. I limped the car along for all 3 runs on both days, but it lost almost all of its braking ability... anytime the brakes were pushed, the fronts locked. I never even knew how much this car relied on ABS!



We got back to Texas, tried a bunch of things, bled everything, new pads, but it wouldn't stop. Tried it in track, and it still sucked. Then we replaced the ABS computer, which had condensation inside of it we later found. Viola! The car was a beast under braking again. Lesson learned: this car without ABS wouldn't stop worth a damn.

Then there's racing the wet. Oh boy, TGFABS! If anyone thinks they can modulate 4 brakes simultaneously with their one foot, hundreds of times a second, they are dreaming. Independent modulation of every wheel (or almost every wheel - even a 3 channel system is better than none) is impossible to do without the aid of ABS.



And I've used E30 ABS many times, too. When we were tracking and autocrossing the '91 318is I got it into ABS all the time. Even on track I'd abuse the brakes to build a gap after passing a faster car by braking deeper - engaging ABS. This car with stock brakes and just good pads could out brake lots of serious hardware. No, the early systems (mid-1980s) are not as fast or as "good" as the later systems, but they are still a great fail safe, and still better than no ABS. We're relying on the ABS in our V8 powered E30 $2010 GRM car as well - and you better bet I'll be engaging that system. :)

There were only a few ABS systems that were truly horrible. There were some early systems that used a 2 channel ABS systems, circa 20-25 years ago, that were worse than having no ABS. On FWD cars with a 2 channel if you braked into a turn and the inside rear tire would leave the ground it would lock - releasing the brakes the opposite corner. This would be the one tire that was already doing most of the braking, so you'd blow the corner. I remember an autocrosser with a 1990 Sentra SE-R that was faster with the ABS disabled. But that car was the exception, and even the simplest of cars had 3 channel systems, as did all of the early BMWs I've seen.

I've also managed to get 2 cars into an "ice mode" that freaked out the brakes. Out of all the dozens and dozens of cars I've autocrossed for 23 years, it happened 2 whole times. Once was with a late 1990s GM car (Firebird) and the other was my 97 M3. On each car it happened one time in many many hundreds of autocross runs they were both put through. Each time it was a weird situation that caused the brakes to release when ABS was engaged, but both situations were avoidable. I was abusing the brakes on both cars each time, and both times it happened the cars had R compound tires and were braking under severe yaw and over a big bump (on top of that the Firebird had a solid rear axle and torque arm rear suspension that would axle hop under abrupt braking). Both cars were sluing sideways, over a big bump that caused a tire to leave the ground, hard into ABS. Freaked the ABS computer out both times, exceeded some set of variables somewhere in their code, and the computers went "oh hell, I don't know what to do!". Point is - its REALLY rare on a modern (1990+) ABS system to go into ice mode - you really have to work at it to manage this. Both times I was over-driving the living crap out of each car and trying for a "hero stop" to cover my mistakes. ;)

In summation: Racers that disable ABS are either forced to (rules), racing in some horribly old car, or are not performing proper testing... ABS IS FASTER

[psyber_0ptix]

^i'm not doctor, nor do i play one on TV, but I approve.

[Massive Lee]

ABS IS FASTER

Hi Terry

If F1 ABS made the car faster, the same technology was not used on e30s, nor does it achieve the same results. Remember the days when US cars had that brand new gimmick called ABS, while have rear drums? Not all ABS systems are the same...

On the e30, if one wheel starts locking, ABS will release all four wheels instead of only the locking wheel. Basically, when you need to brake the most, ABS will release the three other wheels that still have grip, and you go into the dirt... e36 ABS was a bit better. Then e46 ABS is 4 wheels independent, and therefore a much better technology where I would agree that ABS is faster.

So, while ABS can make F1s faster, they'll make the e30 dangerous for track duty. It was initially designed for your aunt Margaret who only knew on-off braking... ABS also makes a car faster, but if driven by racers who have no clue of threshold braking, or use lousy brakes. I know of several drivers who pride themself of continuously hitting ABS and counting on it... Get proper calipers, and the feel becomes instantaneously much better, allowing to better feel the brakes. Then, you might not need ABS anymore. :pimp:

[agent]

You can't change to "proper" (which I'm assuming when reading your post means "my") calipers in SE30. Good luck with convincing the numerous SE30 drivers here that their cars are "dangerous for track duty" or that they are "racers who have no clue of threshold braking, or use lousy brakes."

[Fair!]

Hi Terry

If F1 ABS made the car faster, the same technology was not used on e30s, nor does it achieve the same results. Remember the days when US cars had that brand new gimmick called ABS, while have rear drums? Not all ABS systems are the same...

On the e30, if one wheel starts locking, ABS will release all four wheels instead of only the locking wheel. Basically, when you need to brake the most, ABS will release the three other wheels that still have grip, and you go into the dirt... e36 ABS was a bit better. Then e46 ABS is 4 wheels independent, and therefore a much better technology where I would agree that ABS is faster.

So, while ABS can make F1s faster, they'll make the e30 dangerous for track duty. It was initially designed for your aunt Margaret who only knew on-off braking... ABS also makes a car faster, but if driven by racers who have no clue of threshold braking, or use lousy brakes. I know of several drivers who pride themself of continuously hitting ABS and counting on it... Get proper calipers, and the feel becomes instantaneously much better, allowing to better feel the brakes. Then, you might not need ABS anymore. :pimp:

Lee,

I'm not going to argue with you - you definitely know more about E30 brakes than I ever will. :p But... I think there might be some variations within the E30 ABS systems, maybe? If I recall ABS was available on the E30 from I think 1986 thru the end in 1991, and you know how BMW likes to tinker with things every year. :)


Left: The 3 channel system on our 325e. Right: The ABS unit on our '91 318is at least LOOKS different

I just looked at the hydraulic ABS units from the '86 325e we have and the '91 318is we used to own/race, and they look different. Maybe the later E30s got a newer ABS unit and/or updated programming? I just know that our '91 318is ABS system worked remarkably well to me, and when I engaged the system on track or in an autocross it modulated admirably - pretty good for 1991 technology.

Since I started racing regularly in 1987 I have had a chance to drive a lot of cars and have been able to experience some good ABS systems and the "early" ABS cars that were a crude, slow, faulty designs. Its funny, but even as far back as 1986, Chevrolet had a stellar ABS system on the Corvette... but most of their other cars had pretty BAD systems up into the mid 1990s. Very slow pulsations, crude 3 and even 2 channel junk. To me the '91 318is ABS system didn't feel like those dated designs. Now the 3 channel system on our '86 325e might prove to be an epic failure - I don't know yet. I hope not, but I won't be surprised if your remarks of it being "dangerous for track duty" turn out to be 100% true! ;) In fact, I suspect that might be the case...

If the '86 ABS proves to be junk we'll just do a transplant from an E36 3-channel system with the hydraulics, sensors, wiring and ABS computer - since the rest of the braking system will be already be from that E36 model (calipers, rotors, master cylinder), why not the ABS, too?

As for the E36 chassis, there were both 3 and 4 channel systems, and I suspect various programming and solenoid iterations from 1992 thru 1999 as well. The later M3's 4 channel ABS is admittedly better, but even the 3 channel E36 M3 system was top notch. The '95 M3 had 3 channel whereas the '96-99 M3 had 4. This worked stupendously well on our E36 LS1 car with the 95 M3 bits all around - when the computer wasn't fried. There was a switch on the 325/328 as well, and I think the traction control equipped cars had the 4 channel? I'm not 100% on that, but I've seen both types on the non-M E36 chassis. The ABS on my '97 M3 is 4 channel, and it is superb both on track and in an autocross.

So, Lee you might be right. The vast majority of the E30 ABS systems might indeed be pretty bad, an "on/off" sort of thing. But from the track/autocross experience I have on that '91 E30, at least, I didn't see that as being the case.... the ABS modulated well and never turned "off" the brakes on me. And I am a self-admitted ABS junkie - I look for that edge and try to hover right around the engagement, but often overstep the limits. Again, I suspect there were several E30 ABS variations, as the E30 chassis saw the dawn of ABS at BMW - it was a learning experience for them (and their friends at Bosch), I suspect. :)

As for being a better driver and not needing ABS... again, factory brake proportioning isn't always perfect and sometimes they rely on the ABS to keep the front/rear from locking up. I've driven some stock brake system equipped cars with the ABS disabled and its usually a step in the wrong directions. I've also driven more race cars with poor brake bias than good bias, and many cannot keep up with the modern systems on sports cars. I've also driven race cars and even factory sports cars with "real brakes" (AP, Alcon, etc), and yes, they can and do feel and modulate better than a car with crappy stock sliding calipers... but you still cannot modulate a "good race car braking system" hundreds of times a second, independently across 4 corners. This is one thing a computer can always beat a man at, especially a man pressing on one brake pedal.

I will agree that on track in normal (club racing/HPDE) dry conditions in a sedan based car you are probably not normally braking 100% threshold into every corner on every lap, and that makes modulation easier. Most tracks also don't have corners where you have brake over bumps, changing surfaces, or brake into a corner pitching the car around a cone - all situations you will see in an autocross - in that sport ABS is a miracle worker and lets you get away with much more transitional maneuvers while still maintaining composure under heavy braking. When I switched from non-ABS cars to ABS sports car in autocrossing, my driving style changed DRAMATICALLY. I also got magically "better". :p



Then there is the "rain factor" - again, the top racing drivers in the world cannot avoid locking tires in the wet. Back when they all had ABS they were all magically perfect braking gods, but as we've seen in 3 of the first 4 F1 races this year that had wet conditions, there are only a very few men in the world that can be pull of perfect deep braking/passing maneuvers in the wet without ABS every time. I'm not one of those men, and never will be. ;)

Cheers,

[nando]

I think Lee might be wrong about E30 ABS releasing all 4 brakes. That would be silly. It's a 3 channel system though, so it would release both rear brakes in the event of a rear wheel lockup, but it doesn't release both front brakes as well. If you've ever braked hard on a surface where the left and right wheels have vastly different amounts of traction, you'd know what I mean.

[Massive Lee]

You can't change to "proper" (which I'm assuming when reading your post means "my") calipers in SE30. Good luck with convincing the numerous SE30 drivers here that their cars are "dangerous for track duty" or that they are "racers who have no clue of threshold braking, or use lousy brakes."

NOP. "Proper" means a combination of pads and calipers that don't get easily heatsoaked, then filling with bubbles and becoming "all or nothing" brakes. You assumption is not founded. Using the stiffer ATE calipers instead of the "cast-in-marshmallow" Girlings is a good step toward "proper".

Also, there are indeed racers that have little clue of what threshold braking is and rely solely on ABS. Some of them, and they bragged to me about their technique many times, are long time BMWCCA Racers. Back packers obviously.

[Massive Lee]

That would be silly.

Indeed. And you are 100% correct. ABS was introduced on BMWs 25 years ago. What we now take for granted (4 channel ABS) took a couple more years to be implemented. It's called evolution of a good dea into a better idea.

In the late 1980's (5 years after introducing ABS on stret cars), even Motorsport and Teves struggled with the racing ABS system, until they hit the proper set-up. Let's be reminded that the ABS requirements for a street cars are not the same as for a racecar. Therefore, when using a street-developped ABS system on a tracked e30 (let's not forget either that street tires, R compounds and slicks don't behave the same way), the results might not be optimum. ;-)