Aftermarket ABS controllers/actuators
Moderators: The Dark Side of Will, Series8217
Aftermarket ABS controllers/actuators
I was wondering if anyone knows of any aftermarket Anit-lock brake manufacturers. Not for the Fiero specifically, but for any car, and maybe in the future the Fiero.
It would need to be adjustable by the user (Like a tunable EFI system), and be able to work on most setups, from a 69 Camaro to a Fiero. I imagine these wouldn't be all that uncommon, but I have never seen/heard of them before.
Any ideas?
It would need to be adjustable by the user (Like a tunable EFI system), and be able to work on most setups, from a 69 Camaro to a Fiero. I imagine these wouldn't be all that uncommon, but I have never seen/heard of them before.
Any ideas?
88GT 3.4 DOHC Turbo
Gooch wrote:Way to go douche. You are like a one-man, fiero-destroying machine.
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trying to picture what "adjustments" there could be on an ABS system?
would an ABS controller be concerned about front/rear bias?
I guess it would have to...in the front are locking, and it needs to realease them, I suppose its gotta loosen the rears up somewhat also, to keep the bias....or does brake bias even matter as much with ABS? mostly you wanted less rear braking, to keep the rear from locking & slding out from under you, but if its not gonna lock, this is no concern, and you can have even braking bias?
would an ABS controller be concerned about front/rear bias?
I guess it would have to...in the front are locking, and it needs to realease them, I suppose its gotta loosen the rears up somewhat also, to keep the bias....or does brake bias even matter as much with ABS? mostly you wanted less rear braking, to keep the rear from locking & slding out from under you, but if its not gonna lock, this is no concern, and you can have even braking bias?
if i'm not mistake the basic abs systems pulse all the wheels the same.. only the newer more advanced system that are combined with stability control alter each wheel individuallyPyrthian wrote:trying to picture what "adjustments" there could be on an ABS system?
would an ABS controller be concerned about front/rear bias?
I guess it would have to...in the front are locking, and it needs to realease them, I suppose its gotta loosen the rears up somewhat also, to keep the bias....or does brake bias even matter as much with ABS? mostly you wanted less rear braking, to keep the rear from locking & slding out from under you, but if its not gonna lock, this is no concern, and you can have even braking bias?
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ABS system? Anti-lock brake system system.
Anyway, yeah, I have an aftermarket ABS actuator right here. It's made by Vans.
There was an AMC in Car Craft that had a Corvette (I think) brake system installed including ABS. Can't remember what he did to modify the controller to make sure it operated properly in the different car.
Anyway, yeah, I have an aftermarket ABS actuator right here. It's made by Vans.
There was an AMC in Car Craft that had a Corvette (I think) brake system installed including ABS. Can't remember what he did to modify the controller to make sure it operated properly in the different car.
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donk_316 wrote:Thie thread should have died after response #2
Liability is huge thing but the complexity of getting the right parameters so the ABS computer can effectivley pulse the brakes would be hard to do unless you focused on one specific application. This would be sooo hard to do as an universal application.
I can just imagine, people inputing their own vechile parameters, going out and testing the brakes on the highway and having the fronts lock at 70mph......ugly.
Plus some of the greatest race cars have never used ABS. Just make sure you know how to modulate the pedal.
You guys are starting to sound like OE.
The point is that we want ABS on the car. I don't want to get into a whole discussion into why, we just do. Plus, if we are happy with the system, I'd like to move it to a Fiero eventually.
The car is slated to be a 69 Camaro, and will have full Corvette C5 frame/suspension/brakes.
The point is that we want ABS on the car. I don't want to get into a whole discussion into why, we just do. Plus, if we are happy with the system, I'd like to move it to a Fiero eventually.
The car is slated to be a 69 Camaro, and will have full Corvette C5 frame/suspension/brakes.
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Gooch wrote:Way to go douche. You are like a one-man, fiero-destroying machine.
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ATM machine ( :knob: )
Most ABS's are 3 channel... the handle front wheels individually and the rears as one unit.
Modern and high performance ABS's are four channel.
On a per-channel basis, an ABS has an isolation (solenoid) valve and a dump (solenoid) valve. When impending lockup is detected at one wheel by processing the WSS signal from that wheel, the isolation valve is closed, which prevents more pressure from being applied and making the wheel lockup faster. If the wheel speed continues to decrease, the controller pulses the dump valve to bleed pressure from the circuit. If wheel speed comes up faster than desired, then the controller pulses the isolation valve to increase pressure in the circuit again.
The tuning of an ABS involves a LOT of parameters. IMO, most of these can be eliminated through the appropriate use of feedback.
The first feedback parameter needs to be comparison of wheel acceleration to vehicle acceleration. This makes it easier to pick out impeding lockups. This also requires installation of an accalerometer either in the ABS unit OR attached to the chassis somehow.
The next feedback parameter involves the brake system. The important characteristic of the brake system is the combination of pressure/torque relationship and volume/pressure relationship. Increasing the caliper piston area increases the amount of torque from a given line pressure. Installing stainless lines and high performance calipers and other modifications to make the system hydraulically "stiff" reduces the amount of fluid that needs to be bled off to effect a certain change in pressure.
This relationship is programmed into OE ABS units, but could not be programmed into an aftermarket generic ABS because the nature of the brake hardware with which it would be used can not be known at programming time. The aftermarket ABS would have to include a pressure transducer on *each channel* to help map the pressure/volume and pressure/torque relationships of the system during tuning.
Tuning, if the software is properly implemented, can be accomplished via an autotune feature like high end aftermarket EFI systems currently have.
Set the system in learn mode and go hammer on the brakes for a while... different speeds, different traction conditions, etc. Eventually the system will dial itself in (the controller can count stopping distance by the number of sensor pulses between brake application and vehicle stop, and then tune to minimize).
It's possible, but as was said above, the big road block is enormous liability in the case of a failure.
Most ABS's are 3 channel... the handle front wheels individually and the rears as one unit.
Modern and high performance ABS's are four channel.
On a per-channel basis, an ABS has an isolation (solenoid) valve and a dump (solenoid) valve. When impending lockup is detected at one wheel by processing the WSS signal from that wheel, the isolation valve is closed, which prevents more pressure from being applied and making the wheel lockup faster. If the wheel speed continues to decrease, the controller pulses the dump valve to bleed pressure from the circuit. If wheel speed comes up faster than desired, then the controller pulses the isolation valve to increase pressure in the circuit again.
The tuning of an ABS involves a LOT of parameters. IMO, most of these can be eliminated through the appropriate use of feedback.
The first feedback parameter needs to be comparison of wheel acceleration to vehicle acceleration. This makes it easier to pick out impeding lockups. This also requires installation of an accalerometer either in the ABS unit OR attached to the chassis somehow.
The next feedback parameter involves the brake system. The important characteristic of the brake system is the combination of pressure/torque relationship and volume/pressure relationship. Increasing the caliper piston area increases the amount of torque from a given line pressure. Installing stainless lines and high performance calipers and other modifications to make the system hydraulically "stiff" reduces the amount of fluid that needs to be bled off to effect a certain change in pressure.
This relationship is programmed into OE ABS units, but could not be programmed into an aftermarket generic ABS because the nature of the brake hardware with which it would be used can not be known at programming time. The aftermarket ABS would have to include a pressure transducer on *each channel* to help map the pressure/volume and pressure/torque relationships of the system during tuning.
Tuning, if the software is properly implemented, can be accomplished via an autotune feature like high end aftermarket EFI systems currently have.
Set the system in learn mode and go hammer on the brakes for a while... different speeds, different traction conditions, etc. Eventually the system will dial itself in (the controller can count stopping distance by the number of sensor pulses between brake application and vehicle stop, and then tune to minimize).
It's possible, but as was said above, the big road block is enormous liability in the case of a failure.
Last edited by The Dark Side of Will on Fri Jan 20, 2006 11:54 am, edited 2 times in total.
if I was to try & put ABS on a Fiero, I would use the system from a Grand Am. simaler drive trains, simaler weight, simaler brake system - and I care not about the different front/rear bias due to Fiero's midengine design - dont think it will matter.aaron wrote:You guys are starting to sound like OE.
The point is that we want ABS on the car. I don't want to get into a whole discussion into why, we just do. Plus, if we are happy with the system, I'd like to move it to a Fiero eventually.
The car is slated to be a 69 Camaro, and will have full Corvette C5 frame/suspension/brakes.
especially considering the fiero came with a horrible front engine brake bias to start withPyrthian wrote: if I was to try & put ABS on a Fiero, I would use the system from a Grand Am. simaler drive trains, simaler weight, simaler brake system - and I care not about the different front/rear bias due to Fiero's midengine design - dont think it will matter.