Brake Effort OK? Need Advice

I'm a newer owner of a 1974 Valiant with 318 and factory power disc brakes. The power brakes require a lot more effort than I am used to. There is definately power assist - but pedal effort seems high compared to newer cars. Is this normal??

The previous owner had replaced the front pads and calipers. Also he replaced the rubber hoses all round.

I checked the idle vacuum right at the booster and got a steady 18"

The brake/front end shop I do business with does a fair number of classic cars. The technician noted that the amount of effort may be normal; newer cars are more "refined" and may need less effort. The technician was not convinced there was a problem. But he wasn't sure there wasn't a problem either. Separately, he found the rear drums were warpped and he replaced them.

Those of you with factory power disc brakes of the same vintage: Is is normal for your Mopar to have a higher pedal effort compared with more modern power disc brake cars that you have driven?