Yes. I understand that principle. That is the first thing ive tried playing with. On the older twin cylinder setup, i modded it so that it had the most lever multiplication you could get. I shortened the cylinder side of the lever so much that the spherical rod ends on the end of the cylinders actually touched the pivot bolt. Still couldnt make that one work.

With the STi cylinder, i have 4 levels of adjustment and they still arent enough. But on the more extreme settings, the lever has way too much travel. Im sure in theory if i took it to the extreme and built a frame with an ever higher ratio it might work. But the lever/handle would be so long, and id have to pull it from the dash into the back seat area ro make it work. Like that old saying "give me a lever long enough and ill move the earth"

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Doing it for all the wagons out there

I dont think its a problem with the lever ratio. Im still thinking its more a problem with the area ratio of the master cylinder to caliper piston.

Changing the ratio of MC to caliper is a bit like changing the lever ratio. If you have bigger caliper, then the brakes work more per unit of force input, but the trade off is the MC travels further in order to fil larger calipers.

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Doing it for all the wagons out there

Bram...you have Brembo's on your car, yes? The setup you bought from me was fitted to STI Brembo's and worked perfectly...so theoretically it should be the same in your car.... there must be something different in the way you have set it up.
Did you chat to MMS?

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No Subarus currently owned

Id be fucking the ABS off bud , thats the main difference . Have done at least 10 of these setups when I was at PBMS . None with ABS never had one issue . Done 2 of my old Datto 1600s no issue . S13 Silvia for a mate no issue . Tx3 turbo rally car no issue . Gemini using hydraulic drum brakes No issue .


None had ABS and None used the factory proportioning valve all had Willwood or AP manual adjustable valves.

It is something i want to avoid if possible. I cant say its not the problem until i either solve the problem elsewhere, or remove the ABS and it does or doesnt solve the problem.

But theoreticaly it shouldnt be the ABS. The important stuff is everyrhing between the HB MC and the rear brakes. Everything before the HB MC is effectively just a reservoir for the HB MC. Look at how a master cylinder works. They have an in and an out. The in is just a resivoir, the out is the circuit to the brakes.

I could unscrew and block off the input to the HB MC and just put a simple resivoir in its place, totoally bypassing EVERYTHING before the HB MC and i can guarantee it will still be the same.

The only issue i can see the ABS could have is because it has a individual circuit for each wheel, you need to use a twin/tandem MC, so you keep both sides independant. But, i am using a group n tandem master cylinder designed specifically for cars so they can keep diagonal split dual circuits (part of the group n regulations). So that should be a null issue.

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Yes. The brembo 2 pots.

If that is the case then it could only be one of a few things.

A plumbing issue. - i have plumbed it in an un-conventional way.
A pad compound issue. - i do have street pads, i would presume most race cars use race pads.
A lever/mechanism issue. I did try and replicate the important dimensions when i built mine? But who knows.

I havent spoken to MMS yet. I presumed they would be shut over the break.

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Doing it for all the wagons out there

Bram, I would say either plumbing or mechanism.....

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No Subarus currently owned

Do you think pad type would have much bearing?

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Doing it for all the wagons out there

I doubt it very much.
ABS could be an issue though...

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No Subarus currently owned

Some more details on the lever ratios etc.

The original handle that came with the cylinder has 43mm from fulcrum to cylinder. And 300mm long handle to fulcrum. That is a lever ratio of 6.97:1 (basically 7:1)

My frame has 4 hole positions on the frame and 7 hole positions on the lever so can adjust quite a number of different ways. The shortest distance from fulcrum to cylinder is 40mm and the longest is 75mm. My lever and Hoonigan handle is 400mm long when at the 75mm hole and 435mm when at the 40mm hole. So that can give me a lever ratio of anywhere between 10.87:1 and 5.33:1. As said, i tried to replicate the ratio seen on the original handle and have adjustments to go either way.

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Doing it for all the wagons out there