Good to hear that you’re so close Chris,
Brings back memories of the final engineers fix up list I had back in 99.
2 and a half metres of chook wire fixed my noise problem.
Not sure why your drivers side would be locking before the passengers, but I can shed light on the front to rear bias.
You may want to take a drive to ABS Brakes in Ferntree gully.
I think they have a brake dyno.
One guy in the club recently took his 4 spotters off and put on 3 spot front calipers on to great affect for front to rear bias.
I recently changed my front calipers thinking it would be a quick cheap upgrade (but nothing is that simple).
Changing the single piston HQ caliper to a 4 piston BMW caliper greatly increased the braking on the front of the car to the point that the rears just couldn't keep up.
My solution was to change the master cylinder to a model that didn't have a crack point (ie: a pressure switch that stops further pressure being applied to the rear brake during hard braking when weight is transferred to the front of the car).
The master cylinder I used was a ford one tonner. That ute came with an auto adjustable bias depending on the weight you were carrying in the rear of the ute.
Once fitted I had equal brake pressure to both front and rear of the car (very dangerous, because the rears would lock up easily under hard braking).
My understanding of a matercylinders brake bias is:
If you are driving at 80kmh and apply the brakes gently you may be placing 500 - 700 psi of pressure through your brake lines to both front and rear and the car will pull up nicely using all brakes.
But if you are traveling at 80kms and have to emergency stop as soon as you hit the brakes HARD a full 1500psi of pressure is applied. The bias switch will be triggered at around 500-700psi and limit pressure to that amount to the rears. As you slow there's a large weight transfer to the front of the car lifting weight from the rear. Hopefully that 500-700 psi is just the right amount of bias to stop the rears from locking before the fronts.
So when I put the new master cylinder in I had to fit an after market brake bias controller (from Wilwood).
I used the Calder park test day to dial it in and as I mentioned in a previous post, the car has never stopped better.
I'm guessing because it has been set up to be so well balanced in the dry conditions, I will need to adjust it if we have a rainy day out at a race track (but I don't mind).
The only other point that I should bring up is with the better fronts fitted it is easier to lock the fronts before the rears in an intermediate braking situation (this being because the fronts are working better than the rears with the same amount of pressure in the lines before the bias switch cuts in).
May have done it all different in hindsight.
But I'm very happy with the end result.
If you do fit an adjustable bias control it will need to be under bonnet to pass ADRs as it is not considered legal to be able to adjust the brakes from inside the vehicle.
Good luck mate, You're so close.
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