ANTI LOCK BRAKES

Someone figured out how to use the simplified anti lock brakes system from the late 80-90 trucks. A pick up was installed on the ring gear and whatever sensors and mods to the MC. It was in some magazine. Looking to do the same with an early '70 A body. Anyone have the formula and are the parts still available? Thanks

I know this is not your question, but I would wonder if 80-90's PU abs technology adapted to an a body with whatever the intended purpose is, worth the hassle,etc, vs say just bigger front brakes/stickier tires?

Mopar Action magazine had this article.
OP is on the east coast where snow and ice are common. I can see the benefit there as opposed to drier and warmer climates.

Parts are getting very hard to find for those old systems. They never worked very well either, more of a glorified adjustable proportioning valve than a true ABS system. True 4 channel ABS is one mod that I'd love to have for my classic car, but doesn't seem like it's going to happen.

aftermarket ABS setups are not cheap.

http://www.bosch-motorsport.com/media/catalog_resources/ABS_M4_Brochure_epdf.pdf

I agree, however in some of these 6 figure $ plus, hey look at me 600+hp retromod cars, street driven by over the hill drivers I am not convinced can handle driving a 4 wheeled office chair, I would think the benefit of an aftermarket Bosch ABS would be a no brainer.

ABS for autocross can be a bonus or a curse. If it's hooked up the the rest of the car like my Porsche it's a curse as it pulls back the throttle and takes it out of sport mode. So you learn fast how to stay out of it. If it is a stand alone system it can help on the street. I don't think that it would be much help on a autocross course as you modulate the Brakes and toss the ass around, that is not good for ABS.

I wouldn't mind trying to implement something if I had the right pump. I have a undriven and driven wheel speed sensor and can pretty accurately detect a rear lockup condition.

My current bias is setup for the front to lock just before the rear, however.

I was wondering what the nascar guys did in the 80's and 90's say at Sonoma or better yet Watkins Glen. Taking a heavy car and throwing it into the turns must have been interesting. I'd figure that the good ole boys came up with something. Not any computer technology back then.

It's essentially a surge suppressor

http://www.73-87.com/7387garage/chassis_suspension/lbs.htm

http://www.larsenracingproducts.com/products/lock-resistant-brake-system-lbs.html

Interesting maybe worth looking at

Its really great when members on this site help solve a problem. Thanks

When IMSA allowed the GTD cars to use ABS, the Bosch Motorsports unit, they improved their lap times by almost 3 seconds. In fact, even though they are considerably down on power and aero to the GTLM cars, they run close lap times.

Yes I have it on my car, but my logic is simple. A set of tires cost $1500+. Flat spot 4 sets and the unit has paid for itself...with the benefit of faster lap times and better control.

Craig, if anybody here is flat spotting 4 sets of $1500 tires, they definitely should stay away from wheeled office chairs. My original thinking was hard street driven all weather, high dollar cars, to reduce cost of shunts and hospital bills. However your example works.

So tell us, how complex/involved is it properly dialing in a custom aftermarket ABS system?

Are there different selectable settings for track/street/etc use?

What car are you running it on?

The systems itself doing ABS isn't that hard, other than the tone rings and the wheel speed sensors in the wheels.

The thing about it is you need to know a lot about your vehicle, especially if you're looking for a yaw-rate sensor, or any type of ESC. Then there's calibrating it. Probably not too hard to do for a big race team. The OE's spend at least a few months calibrating factory ABS (and years when you think about all the other features in modern cars)

Sounds like in the Bosch unit mentioned they are doing BTCS (Brake traction) and EBD (electronic brake force distribution). This can really help the balance on your car and therefore improve lap times.

You won't be able to use a modern one from a Charger or whatever because of the in-vehicle bus communication. Otherwise the hardware would be pretty adaptable.

The Bosch M4 Motorsports unit is identical to its OE counterpart, they differ only by programming. The M4 has 9 preprogrammed maps adjustable from a rotary switch (full wet to grippy dry). It also has 2 programmable maps. Just 2, so the 9 that the Bosch engineers preprogrammed are pretty damn good.

When you set it up, you enter your car data, weight, tire size, CG, etc, etc. The included 3-axis G-sensor and wheel speed sensors are the input data to the unit.

This is a Motorsports piece, so you have to have the Bosch Box II adaptor to connect to a laptop! That's another 1K.

I'm running a Motec system on the 'Cuda, so I use the wheel speed data from Bosch unit to feed the Motec for Traction Control.

I run a floater rear and big bearing hubs, so I machined the rears to accept a custom tone ring and made an adaptor that doubles as a seal retainer for the front:

[/quote] What car are you running it on? [/quote]

This one under construction!

As I said, not cheap. but that sure looks nice

That's fancy looking. I pickup undriven speed from the rotor vanes, works well.

Genius

That's killer, talk bout thinking out of the box. I've never seen that before, or thought of it myself. Well Done! @ CJD did you build your own harness or did Bosch supply a "A vehicle specific wiring harness is included in the Kit."

I bought the Club Sport kit. It comes with a long harness to fit about anything.

Elegance of K.I.S.S.

Are those hall effect sensors?
Thought hall sensors like square edge teeth, and thats hard to do on a rotor, but if it works so be it.
Do they handle the potential heat load in that proximity?
Its a straight or curved vane rotor?

Nice, that car looks like a max effort machine. Fabbing that kind of harness would be a PITA, doable though. After wrenching for 34+ years now I'm getting to a point where doing everything just isn't how I want to spend my time. I'd still double check every crimp and connector just to be on the safe side. There's too much 3rd world "craftsmanship" out there.

Yes, it's a hall effect sensor. The vanes themselves are straight with rounded edges. Not having sharp edges doesn't seem to be a problem, having that many teeth makes for a pretty high resolution signal.

You can see the first and second gear wheelspin [vss1 = rear]

From there I have some tweaking to do to the tire diameter input for them to read exactly the same at speed. They average 1/2mph apart right now.

I talked to the guy that developed it some years ago, when I was building Warhammer. My understanding of this items was that it was a type of surge suppressor. I never ended up running one so I can;t help there.

Seems the items is at http://www.larsenracingproducts.com/brakes-calipers-supporting-and-replacement-parts/

Would the surge suppressor be used in place of or in conjunction with a proportioning valve on the street? Has anyone used the brake fluid recirculator to cool fluid on a street car? Seems both of these products would be a good idea for a 74 d100 that I occasionally use to tow. Thanks ahead for any input.

Ehrenberg covered this conversion in Mopar Action 2 part Oct/Dec 2012 issues

The "surge suppressor" is just going to delay the actuation of the rear brakes, all the consumer versions of this type of product were proven to be useless at best and dangerous at worst. As far as brake fluid, just flush the fluid with some good high temp DOT type 4 fluid and make sure the brakes are in good shape.