Need advice on brake setup
Posted by juwyro@reddit | projectcar | View on Reddit | 8 comments
I'm trying to get the brake setup on my car to work right in short. It's a 77 MGB with stock front brakes, Mustang rear discs with an 8.8 swap, stock booster, and I've tried a few different master cylinder sizes. The car has a K20 swap with ITBs.
So far I've had the stock master cylinder, and a 1" master on the car with pretty much the same results, a soft pedal until it gets to the bottom of the travel then has pressure. I've put a 1-1/8" master on it now and have a nice firm pedal, but with the ITBs producing no real vacuum at idle the booster doesn't function much.
I've talked to Wilwood and they suggested a 1-1/8" master to go with my brakes. The fronts are 2" pistons and the rear are 1.5".
My last thought is to swap to manual brakes with the 1-1/8" master. Doing the swap on this car won't be too difficult making a mount and changing the pedal ratio.
The real question is is this the way to go? Or any other suggestions? Vacuum pumps, hyroboost, and reservoirs aren't really a solution for me, neither is changing the engine.
rudbri93@reddit
I did the whole 'delete booster and move leverage point' on my e30, with some ebc yellow stuff pads it works great.
juwyro@reddit (OP)
What pedal ratio did you go with?
rudbri93@reddit
welllll its kinda custom. I used a kit that came with a template, but it wasnt enough, so i welded that hole shut and went up about an inch.
Here is the starting point i used, but i dont have a measurement for it.
juwyro@reddit (OP)
Like yours my whole car is nothing but custom stuff. I'll just measure for a few different ratios, drill holes, and see what I like.
rudbri93@reddit
its annoying and tedious, but it works. Also take into account pad compound, throw some stuff with good cold bite on there.
juwyro@reddit (OP)
Also a money pit. This is really the last big thing to sort on the car.
I think it has some kind of Hawk autoX pads right now.
trucks_guns_n_beer@reddit
In the late 90’s into the 2000’s a lot of cars had rear disc brakes as an option. These cars had what I believe were called residual valves, inline between the master and brake. They held a little pressure on the line, making the rears actuate sooner, which you want. I think it kept them from having to use different master cylinders. Just googled residual valves Comes right up.
juwyro@reddit (OP)
I should've added I did those. They kind of worked, but the brakes were noisy just driving around.