josh19wrc

So,

Anyone here know how ABS systems work?

I've decided that I'm going to try to make the AWD in the power wagon active AWD.

The NP203 is full time 4WD... Its NOT AWD. There's the problem. The 203 has a center differential that is open to allow front rear differentiation. However, when one end of the truck looses grip, I lose the ability to drive the wheels with grip, as all the power goes to the end with the least grip. I'm already planning on putting a lockright locker in teh rear, and a detroit torsen in the front, so, it will drive both wheels on whatever end it send power to, but...

Here's my idea:

Get the yokes on the T case outputs custom machined to accept a splined hub. slip the hub on, and bolt a brake disc to the hub. Now, there is a disc on the front and rear outputs of the transfer case. Put a caliper over each rotor, and hook it up to an ABS pump.

Put ABS sensor rings and sensors on the front and rear driveshafts, and have an Data Aquisition or a simple input/output ECU monitor the driveshaft speed. If it varies by more then X percent (TBD, I need to do the math and see what the difference in shaft speeds front/rear is at full turning radius, but I estimate it at around 8%), the ECU applies the ABS pump to the shaft that is spinning faster. This will make the power go to the slower moving shaft, and Voila, Active AWD.

Now, I know that ABS pumps should have no issue suppling the pressure and such, and, the sensor rings are no problem, the issue is writing the software and finding an ECU. I'd like to hear thoughts on wether you think I'd be better off trying to "hack" some sort of stock ABS controller, or, trying to write my own using an input/output controller?

igotnothin

cool concept. Im thinking if you know how to write the software to do it, that will be your best bet..
But i dont know... Looking forward to seein some pics of this..

Smith-02

you realize that 80hp overpowers stock brakes right?

solid concept, but you need to think about your braking setup a little more. drums would be a good idea, like 1ton and up service vehicles use (the parking brake on the driveshaft)

i have a d20 t-case (2.03:1 low, single stick) you can have for scrap price if you wanna ditch the center diff

josh19wrc

thanks, but, It currently has a 205 in it right now, but, the 203 is the only case other then the Military hummer case that can be run in 4x4 on dry pavement and not eat itself. Teh Mil spec hummer case is teh 242 HD AMG. ITs hard to find, expensive, and, the drop is on the wrong side of the truck. I could flip it over, but, its got an oil pump in it because of the temperatures AWD generates. If I flip it over, the pump obviously wont work.

As far as overpowering stock brakes, what brakes do you mean? I was going to run like 4 piston RX7 caliper on a 10" rotor on each shaft. ABS pumps can put out like 2000 PSI. I also dont want to stop the driveshaft, just drastically increase its drag to make the power find the least resistance path, which, would then be the other drive.

Emperor

another sick german

bitchM0VE

More work, but here's what I'd do. Weld up the open diff that splits torque to the front and rear axles. Now, you install a clutch pack betweeen the front diff so you can turn it on and off, and vary the % torque transfer to it by the hydraulic pressure on the clutch packs. That's how OEM's do it anyways. Might be just as simple as what you are proposing. Problem with your method is you're gonna loose a lot of energy to the brakes. If you loose traction in the rear and need to put 100 HP to the front tires, you have to eat 100 HP through the brake thingy to send an equal amont to the front. So you loose 1/2 of your power....

josh19wrc

twin turbo, twincharged 360 V8... she aint gonna be short on power. I could just stick a Jeep Grand Cheroke Quadra Trac case in it (has your aformentioned Clutch pack type AWD), but, those are only rated to 3K ft-lb input. after the multiplication through the trans, the T case will see north of that by alot.

Smith-02

full time active awd is, get a non-diffed t-case.

/thread

seems like alot of extra work for a high hp high torque application that can be solved by simpler means

josh19wrc

and then I'll have fatigue breaked to add to my standard power driven parts breakage. Not to mention the crummy tire wear.

Id love to put a NV242HD AMG out of an H1 hummer in it, but, they are expensive, and, the drop is on the wrong side. Its a shame, they can take like 8K ft-lb input, and have a 60/40 torsen in them.

bitchM0VE

Gonna waste a lot of power if you do the brake idea, and if you have a -----ton of power, you'll overload the brake fast and then it will fail anyway. Beef up something and make it work.