That's a bummer. You say you have the cop MC. That's the 1.25" Maybe in the middle with the 1.125 civ MC?
I plan on doing more troubleshooting, but on this one - the pedal stroke of the vette MC - it's 100% as a result of the MC. During a regular stop, it almost goes to the floor which is too long of a stroke for me. I swapped out the MC yesterday so I am back to the cop one. I may get the OEM one back out and try that, like you suggested.I keeps sounding like you might be bottoming out a piston in the MC which would mean something is taking too much fluid. It would be useful to see if that's the case and which one.
Faulty logic. There is a difference between how the two different boosters amplify user force or GM would not stock two different parts and the aftermarket would not stock the two types. You have made no reference to the different brake pedal designs or which booster you are using. See posts #30,31, and #33. Leverage and boost force are important to braking.The problem is unchanged between boosters and calipers, so that rules that out.
Measuring and reporting pedal stroke might help. Others might then measure/report their pedal stroke if you make the effort to post yours first.The panic-stop/brick wall issue is what I am trying to solve.