Disk Brake Question

[88sub4x4]

I was considering doing a 14BFF disk conversion on my '99 sub, but it has 4 wheel ABS, and the proportioning valve is electronic and internal to the ABS HCU. Has anyone attempted this? Is it possible to convert and still have a functional ABS system?

 

[sweetk30]

i am doing this on a 96 after next week so i will let ya know. and also i am having a vendor make the brackets for me as the price will be much cheeper than the other guys high prices. the brackets are for the pop off drums .

 

[88sub4x4]

Cool, I'd like to get rid of the 100+ lbs of drums. What do you mean by pop off drums. Meaning you don't have to pull the alxeshaft out? Who is making your brackets?

 

[sweetk30]

pm sent to ya

 

[jac6695]

Don't be afraid to share.

Whatcha doing for a parking brake?

 

[sweetk30]

Don't be afraid to share.

Whatcha doing for a parking brake?

we will post up when done. and parking brake will be caddy calipers as always if i run them.

 

[88sub4x4]

I'm not too concerned with parking brake. I do my own inspections so everything is always passing on my trucks. I will probobly install a line lock to use when loading the car trailer though. I get alot of movement if I don't set the e-brake. I'm real curious to see how the ABS is affected on sweetk30's rig, and how it adjusts with brake proportioning.

 

[K5MONSTERCHEV]

Is it 2 or 4 wheel ABS? I dont see how the ABS would be affected at all. It doesnt have sensors on the wheels or anyhitng like that to worry about, but even if it did it wouldnt make a difference. Hmmm............

 

[88sub4x4]

It is a 4 wheel abs unit. It uses 3 sensors. One at each front wheel, and one for the rear wheels. I'm pretty sure the VSS gives it's info as the rear sensor. By having the proportioning valve controlled electronically by the ABS I was wondering if the ABS unit will be able to send the proper pressure to the calipers. If not, will it be able to compensate? Will it send too much or too little? If it sends too little pressure, is there a way to boost it? If it sends too much, and I install an adj. prop. valve will the ABS function normally during a rear wheel lockup? These are the things I am trying to fugure out.

 

[K5MONSTERCHEV]

Trial and error.

The rear ABS sensor is the VSS.

 

[sweetk30]

update : we got the parts for the swap that were custom made. will be doing the swap hear soon as the new week comes and i have time. i will be taking pleanty of pics of the swap and all info to the swap. thanks for being patiente.

 

[88sub4x4]

any updates?

 

[sweetk30]

much closer just need to figure out a small problem with the abs /propotion valve stuff.

 

[88sub4x4]

I played around with the tech 2 scanner. There is no way to do anything to the prop. valve. I was able to actuate the pressure and dump solenoids for each circuit, and run the pump, but I couldn't disable the valve. If we could just get a hold of a unit to take apart and see if we could change a spring in or something. If I do come across a discarded unit I'll let you know. As for me, I bit the bullet and rebuilt my rears. New shoes, drums, wheel cylinders. Stops like a brand new truck now. Both my wheel cylinders were only working the first approx. 1/3 of their travel, and then they hit a rust ridge and would stop.

 

[sweetk30]

i bypassed valve and seems to be o.k.

here is some pics.