drum brake proportioning valve

I converted my 64 Valiant from a single master cylinder to a dual. All four wheels are drum as from the factory. When I step on the pedal I have to stand on it to make the car stop. Many have said I need a drum brake proportioning valve or do I need residual pressure valves? I thought many here on the site said it was not needed. Brakes all the way around are good almost new. I feel as if I am not sure the car will stop I have to push so hard. Thoughts??