DIY Brake System Redesign
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From: Concord, CA
After studying all the various braking combination in all newer p-cars, the is an evolving common theme. High pressure on the front, low in the back and bet your life on ABS.
Now on early cars without ABS, one can logically machine a gear tooth sensor to go between the outside CV-joint and the wheel hub. Now this allows one to create a means for rear ABS and traction control. I have more research on how 951/968/986/993 do their hydraulic gates and logic function, but I have a good idea. So once the brake bias is out of the system and each line is individually controlled, it becomes possible have rear electronic braking assist and selectable modes.
Now getting the modulation of the fronts may not be possible; however, since it is possible to turn the back surface of the hub true, another tooth gear ring could be applied.
Much of these thought come from how my BMW e39 behaves. The fronts are ABS only and the rears of ABS/TC combined. The additional extension with Wilwood electronic brake valve locks mean it is possible to add dual fluid path logic to the system. Disable the ABS (or if it goes into fault mode) the flip-flop valve logic could be used to switch to a back up brake bias for the rears.
Extend this idea to use three bias flavors 5/55, 5/44, 5/33 to get selectable behavior. So rear ABS enabled or disable with three selections and defaulting to 5/33.
Yes I have been sniffing way to much brake fluid.
I don't want any other year than MY '81 so please don't say go by an newer car.
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From: Concord, CA
Bosch has an interesting aftermarket ABS/TCS/EPS kit ...
Valve, sensors, brains
The question is the best way to put gear tooth wheels on the hubs/axles.
Bosch complete brake system
Valve, sensors, brains
The question is the best way to put gear tooth wheels on the hubs/axles.
Bosch complete brake system
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From: Le Mans - France
It seems you added complexity in the system. good luck!
For my race car I would like to found simple way to shut off the ABS Brake system and mount a manually adjustable rear brake bias.
Do you have a scheme of the entire brake system with ABS? How would you do that?
Puyi
For my race car I would like to found simple way to shut off the ABS Brake system and mount a manually adjustable rear brake bias.
Do you have a scheme of the entire brake system with ABS? How would you do that?
Puyi
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From: gone to Pelican - search for reanimotion
Bosch motorsport ABS M4 kit http://www.bosch-motorsport.de/conte.../html/3826.htm
the only generic one they sell that I know of (for a little less than 6000 euros)
the only generic one they sell that I know of (for a little less than 6000 euros)
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Bosch motorsport ABS M4 kit http://www.bosch-motorsport.de/conte.../html/3826.htm
the only generic one they sell that I know of (for a little less than 6000 euros)
the only generic one they sell that I know of (for a little less than 6000 euros)
I have it in my head and on pencil/paper. I have found a supplier of tooth gear rings that can fit on the CV joint and maybe the transmission flange for the axles.
The same supplier also makes rings for the hubs which can be pressed on.
In both cases the smallest order is 100 rings of each
So the budget for this fun is in the $10K range now; however, finding a wrecked car with the all the pieces (yeah, why did the system not work, hoping to find a DUI car).
I am open to more input folks.
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http://www.alibaba.com/product-gs/27...BS_SENSOR.html
http://www.alibaba.com/product-gs/24...NSOR_RING.html
Two styles of rings in mind, the hard part is getting the trigger on the turning surface.
http://www.alibaba.com/product-gs/24...NSOR_RING.html
Two styles of rings in mind, the hard part is getting the trigger on the turning surface.
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http://www.ebay.com/itm/220950468389...84.m1423.l2649
Ford Mondeo 3/40 is one of the bias units I have considered, but would like to know how it matches against the ATE/Porsche 5/44.
Ford Mondeo 3/40 is one of the bias units I have considered, but would like to know how it matches against the ATE/Porsche 5/44.
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First is the replacement of the 5/33 bias valves with two ATE brass tee's and a new small tube for the flat crossover. The second show the new tubes made so I could save the originals in case I need to install the the pair of 5/55 bias vales I got from Tony77 today. Now with a new brake booster added the hot idle now seems more sane.
Band news is with all brakes being equally pressured the first tests from 30-0 still produced front lock ups; however that was extremely deep in the pedal and with a slight release of the pedal the stopped the slide and continued to brake extremely hard. I was not expecting to be basically to be nearly ejected out of the seat into the steering wheel while being sliced in half by the seatbelt!
At this point, I wonder what kind of pads I should switch to in the rears and should the rear rotors be vented and cross drilled also?
Does anyone have a 5/65 bias that I may want to setup for the front reduction when I later go in and reconfigure and fully split the front and back in to equal pressured pairs.
Tomorrow I will try 40-0, 50-0, 60-0 and so in a straight line and then maybe some light curve braking to see if I get any single lockup or funny pitch and pull.
Band news is with all brakes being equally pressured the first tests from 30-0 still produced front lock ups; however that was extremely deep in the pedal and with a slight release of the pedal the stopped the slide and continued to brake extremely hard. I was not expecting to be basically to be nearly ejected out of the seat into the steering wheel while being sliced in half by the seatbelt!
At this point, I wonder what kind of pads I should switch to in the rears and should the rear rotors be vented and cross drilled also?
Does anyone have a 5/65 bias that I may want to setup for the front reduction when I later go in and reconfigure and fully split the front and back in to equal pressured pairs.
Tomorrow I will try 40-0, 50-0, 60-0 and so in a straight line and then maybe some light curve braking to see if I get any single lockup or funny pitch and pull.
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From: Concord, CA
60-10 and 70-30 data: Given the asphalt road had long swooping dips and rises.
Braking was extremely flat but long in the pedal, and only one lock up event on RF during a dip event. I believe I will need to add 2Lbs or 10Lbs pressure hold on the rear calipers; however, this will be the second step if the next stage of joining the front pair and rear pair on their own circuits.
Design pictures to come shortly.
Also the ABS for the 928 series appears to be 3 port limited with the rears paired and the fronts individually managed. This make me wonder how does the system handle rear corners lifting without completely dropping the braking power on the opposite side being forced down hard.
An actual 4 port system is the direction I am heading now and completely away from the 3 port Porsche model.
Braking was extremely flat but long in the pedal, and only one lock up event on RF during a dip event. I believe I will need to add 2Lbs or 10Lbs pressure hold on the rear calipers; however, this will be the second step if the next stage of joining the front pair and rear pair on their own circuits.
Design pictures to come shortly.
Also the ABS for the 928 series appears to be 3 port limited with the rears paired and the fronts individually managed. This make me wonder how does the system handle rear corners lifting without completely dropping the braking power on the opposite side being forced down hard.
An actual 4 port system is the direction I am heading now and completely away from the 3 port Porsche model.