At present the MC actuation rod angle is 0° at mid stroke. By my calculations if I move the rod pivot point .375 closer to the pivot point of the brake pedal I can get about 20% less pedal effort with around 1/2 more pedal movement. So at mid movement the rod will be at about 5° angle to the MC. Angle acceptable?
As long as the rod does not come in contact with MC I don’t see a problem. I drilled a hole in my pedal to help with pressure. I put a plug (cut bolt shank) in the existing hole. I used fender washers on each side of the new hole to make sure the plug did not fall out. There was not much material left between the 2 holes.
Sorry, don't mean to. Toolmaker curse. At 74 my brain still works ok, [maybe not, got a puppy], the rest of me not so much. !
I've moved the rod pivot point to get a better pedal ratio. When I did it, I drilled new holes, so the master cylinder moved the same distance and kept the m/c rod level. It was a good modification for my rod. I put a LOT of miles on it with an improved brake pedal feel. Here's a pretty good article: https://techtalk.mpbrakes.com/how-to-series/calculating-pedal-ratio
If there isn't room to move the master cylinder up, you could make or buy a tapered shim to change the angle of the master cylinder slightly to get back to 0*.
Remember to account for the reduction in pedal force (F x cosine of 5 degrees)......if you want to be technically accurate......
If the master has a deep hole in the piston that the rod goes into, make sure the rod doesn't touch the sides of the piston at any point of the pedal travel.
I didn't word that very well. I meant make sure the rod does not contact the side of the piston if the piston has a deep hole for the rod to go into. I fixed my original post. Thanks for catching that.
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