Published on March 1st, 2010 | by James Simpson0
Impreza ABS Removal + BIAS Valve Fitting
Back on the car this weekend – was supposed to be doing marshal training, but looked out the window and saw all the snow and decided against it (it was cancelled in the end anyway)
Now that the sound deadening has finally been removed, I can finally get started with the Hammerite Satin Black spray paint (I don’t know why but every time I see satin black I think of Edd China (Wheeler Dealers))
For those of you who don’t know how to remove the ABS and what is needed to put an adjustable BIAS / Proportioning valve in, here’s a quick explanation
The way the standard brake set up works is as follows: You have two lines coming out of the brake master cylinder which then go to a none adjustable bias valve then drop down and goes across to the ABS module. These two lines then come out as 4 lines from the ABS module, split between front left and rear right, front right and rear left (diagonal split). What you have to do when you have removed the ABS module, is to use T-Pieces to pair up both front pipes and both rear pipes, then run one port from the master cylinder to the front T-Piece, then the other port from the master cylinder to the adjustable brake bias valve, then from the bias valve to the rear T-Piece.
With the above in mind, I wanted to keep as much of the existing pipe work in place. as i possibly could, so I made a start of the ABS removal, and what a pain in the arse that was… The standard nuts didn’t want to budge, it was supposed to be a 10mm, but was a little too big and managed to round off the nut, so ended up going imperial with a hammer and got them loose that way (should have got myself some decent brake line spanners.
Once I got the lines removed from the ABS module, I removed one of the lines from the brake master cylinder, and managed to bend the standard rear lines into position to T-Piece them together, ready for a new piece of copper pipe to go directly into the brake master cylinder.
The other line that runs to where the ABS module can stay as is, but will need to be bent to allow you to T-Piece all three front pipes together.
I then mounted the adjustable bias valve in the same location as the standard none adjustable bias valve was, and cut myself a new section of copper brake line, bent it into the rough shape I needed, added my fittings, flared the ends of the pipe and finally fitted it to the brake master cylinder and to the bias valve
Next on the list is to fill the brakes back up with DOT4, and do a gravity bleed on them (just learned about gravity bleeding, so thought this would be a great opportunity to test it out)
Also need to clear out the boot of the car (as its full of all the crap I’ve removed from the cabin) and put up a for sale post with all the interior bits
Waiting on my postman to arrive today with my solder suction removal tool so i can get on with fitting the chip and put the ECU back in the car to start it up (not been run in a while)
Also need to remove the crank sensor and give it a few turns over to fill the oil cooler with oil (I couldn’t fill the oil cooler with oil before fitting it (quite impossible without getting oil all over the place)
Need to fit my new brake pads (2 min job, as I’ve already removed the passenger side)
Need to finish putting all the dash components back together, and steering wheel and seats back in the car.
And give the car a good wash for my secret wrap :D