Along with everything on my list the next few weeks, I really need to replace the master cylinder on my IROC. It appears to have been leaking for a long time, just something I haven't got around to doing yet. My question is, is there anything better on the market than just going to Napa or advance and getting stock replacements? And while i have the system open... Should I replace the proportioning valve? And other than the fun factor, any reason to put a line lock in for the couple times a year I might go to the track?

 

If it's the stock GM Aluminum master cylinder, pop the snap ring out the back, pull the plungers and clean out the 30yrs of gunk. Once it's sparklin clean, look down the bore for damage. Pitting, scoring, that kind of thing. If it's not all chewed up, the springs aren't rusty, etc, pick up a seal kit and rebuild it yourself.

It's probably just me, but I know where my cars have been for the last 20 years. I know how they've been maintained, etc. Even if one of my parts fails, I know the history of that part. I don't know where Juan Jose "The Hone Master" gets his cores, or how good he rebuilds them. I'll put my money on my part generally being a better bet. Also I'm cheap... Er... Frugal. Thrifty? I don't like to spend money on something I can do myself.

If your prop valve isn't full of sludge, clean it and reuse it. A line-lock sounds like a headache and an additional potential failure point, if you don't see yourself using it much.

I remember reading that people have used 4th gen boosters and masters, but really can't think of any reason to do so.

 

Never even crossed my mind to rebuild it. I haven't done that since vo-tech in 1987, lol! I assume it's possible brake fluid leaked into the booster so I should replace that tho, correct?

 

I'm not sure that brake fluid would enter the booster, I'd expect it to run out the bottom between the master and booster. If the booster holds vacuum, I'd probably assume it's functioning.