Old GMC Gold, I have a booster. I just remounted my carb after a very thorough cleaning and exam. But she still stalled on me when I gave hard brakes. I am finding it hard to believe that my carb is not good. I do not think that a carb 'goes' overnight like that, precisely when you do a tune-up. Maybe the booster went suddenly? I happen to have a brand new booster but it is a double pot and I have a single pot right now. That is, I have add a line. I can't just swap it in real fast. But I am going nuts already about this stall-on-braking. Never had it before. Don't know what I did to bring it on.