I am working on a 1966 mustang. Originally the car had manual brakes. I have converted it to front disc with a power brake booster and a dual master cylinder. The manual brake pedal ratio was 6:1. Since the power brake booster attaches to the pedal in the same location the ratio is still 6:1. I have read that a power brake car usually has a ratio of 4:1. Is this a issue to be concerned about?

 

IIRC, there is sticky up top with links to what you are asking about.