rear disc conversion

[twiss]

That's what I put isn't it :p

[SherwoodNash]

I swear I read smaller pistons too? must have been a instant edit

[ScottieJ]

I swear I read smaller pistons too? must have been a instant edit

he edited both posts

Then again the difference in piston size between the aisin and Lucas calipers is so small there won't be much of a difference in force anyway.

[twiss]

Nah you're all mistaken
There isn't that much difference in size... but I get a lot less rear end lock up than I was expecting.
I was planning to see how it went and maybe get a bias valve if necessary... that was about 3 years ago

It's quite funny to do it on purpose though, at low speeds the back tyres make a chirping noise as the tread skids along the road lol

[Anton]

Aisin's are 51mm, Girling are 48mm.

That's 2042.82 square mm vs 1809.56 square mm, or about 12% bigger. Your front/rear bias is about 1:0.88.

I'm running the Rover's on the rear, which are 30.2mm (716.31 sq mm). My front/rear bias is about 1:0.35. Ideally you want between 1:0.5 and 1:0.33, so I'm on the low end of that scale, but with SPOA that's probably a good thing due to brake dive.

I want to remove the brake bias valve as it's designed to provide a small amount of pressure constantly. This is causing my SJ to eat up rear pads every 1000 miles or so. Drums need a tiny bit of "preload" pressure apparently, so the bias valve does that. With my brakes set up the way they are, there's no need for a bias valve at all, so at some point I really need to get under there and rip that thing out.