BPS

My ABS hasn't been working for a while and I now have a 12 bolt without ABS so I'm looking into how to remove that ABS tree from the engine.

I've done a search and there seem to be 2 suggestions - one is to disconnect and plumb the hoses into the master cyl.

The other suggestion is to go through an impala proportioning box first I'm not sure if this box different from proportioning valve sold by many aftermarket firms (http://cgi.ebay.com/ebaymotors/ws/eB...tem=2454488897)

Anyway, so has anyone done this successfullt on an LT1 and can you provide - suggestions and part numbers if necessary.

Thanks

PatriotTA

TTT

I want to know how to do this as well.

aram

I did it on my LT1. I tore out the old ABS unit and then used my line lock to "t" together the front two lines (after I cut and re-flared them with standard fittings) and then ran a new line to the mast cyl. Then I ran a line from the mast cyl to a wilwood adj. prop valve that i mounted where the fluid resivoir is for the clutch on manual cars. Then I ran a NEW line from the prop valve all the way back to the rear "T" line of the car. Problem is the rear fitting going into the "T" is bubble flair and a really weird size so there is no adapter i could find. Since my car is in storage I never finished it but I found a local place to remake the rear "T" by the axle except with a standard fitting pretty cheap. Next time I go up to my car I am going to install the rear line and adjust the proportioning valve to make sure everything is working right. I did drive 50 miles to store the car with no rear brakes and didn't even notice it honestly (no quick stops though).

BTW it was a royal PITA and I would never have started it if I knew it would be such a pain. The only really hard part was the rear line and re-flaring a lot of the stuff while it was in the car as well as finding all the fittings. Autozone had a pretty good selection actually. At least I feel I could re-plumb a brake system from scratch now.

It is 10-11#'s off the front of the car though (weighed ABS unit and bracket).. which is a LOT of weight if you think about it and it does clean up the engine bay a lot. I probably spent over $100 to do it by the time I bought everything though.

I have some pics but they are crappy.. you can kind of see it here in some of the pictures in my album:

http://f2.pg.photos.yahoo.com/ph/ara...dir=/green+car

dnz28

http://web.camaross.com/forums/showt...hreadid=202032

I1O0O1I

ttt, would like to hear some more too

aram

What else do you want to know? When you remove the ABS it becomes exactly like all those braking systems without ABS. You have to re-plumb the lines and install a proportioning valve so the rear brakes don't lock before the fronts do. The only thing that makes it difficult is that GM uses metric fittings all over the place. The easiest way I found was to replace all the metric fittings except on the mast cyl.. there I used two adapters from metric to standard. Nothing too crazy, but you need to know how to re-flare brake lines.

PatriotTA

Aram - thanks for the info. One more thing: how much did the prop valve cost, and do you have a part # or anything for it? Thanks.

BPS

rather than reflaring the lines and fussing with adapters can't we use high pressure compression fittings combined with a little pipe bending?

aram

I would not recommend using compression fittings on a braking system and I doubt anyone else would recommend them either (call any brake parts manufacturer).

There is over 1000psi that the lines have to withstand, and even though compression fittings can withstand much more pressure than a braking system needs, they need to be installed correctly in order to work right (I used to work as a lab tech and we used compression fittings for everything) and you also need to use a very high quality brand fitting and line (ie swaglok). I would just go through the hassle of re-flaring the lines for your own piece of mind. Compression fittings _will_ work though, but I wouldn't really trust them. I actually replaced my entire rear line because the previous owner (idiot) of my car decided to use a compression fitting on it for some dumb reason.

The prop. valve I got is the universal wilwood one available in summit and I think it was around $40. I am sure pretty much any adjustable universal valve would work.

1fstTA

okay im gonna go ahead and do this abs delete this weekend. Ive done a lot of research and im ready to take this thing off and have the weight reduction and the added room up front. The only thing im concerned about is the bleeding of the brakes. Ive done everything on this car but bleed brakes did anyone have any problems at all and can you kinda point out the way you did it.

thanks

aram

Don't cut the long hard line that runs under the car to the rear "T". With the brake flaring tool I had I could not flare that tube.. just too hard of material I guess. Might be possible with a really good flaring tool though. I had to replace that whole line, which is what took the most of the time. See if you can find an adapter from that fitting to go into the outlet of the proportioning valve and you will spend half as much time on removing the abs.

1fstTA

okay im a little lost again. I have so many damn lines runing off my abs i dont know what the front and back are man. I have 2 lines running off the master to the middle of the abs and then runing out of the top then I have 3 lines running into the bottom of the abs. man what lines are what. do you have a step by step photo of what comes off of what and what goes where. Im gonna retry this tommorrow. again

Mike

BPS

Lines from the master
the 2 lines out of the master are for front and rear
the line from the master closest to the firewall is the front and the other is th rear


lines from below:
the 3 lines coming up from the bottom of the engine bay into the ABS are comprised of 2 lines for the front brakes and 1 for the rear - 2 for the front should be the same diameter and one for the rear has a larger diameter.

you need to tee the 2 front lines and connect to the rear opening (closest to the firewall) on the master.
the line from the rear needs a proportioningvalve and a is to be connected to the other opening on the master.

Aram - as he explainds below - used his line loc to tee the 2 front brake lines. he then constructed a line from the line loc to the master. For the rear brakes he went from the rear of the car all the way to the master but suggests that you avoid that by getting a proper fitting for the prop valve.

that's my understanding
Hope that helps.

pelebkf

I have question: Could you just run the front to brake lines to the master cylinder via the two opening in the master cylinder and forget the rear.

BPS

only if you want to eliminate your rear brakes and compromise your front brakes.

Not a good idea