I was helping my friend install a brake booster on his 65 charger. After changing the old manual brake MC and adding a new booster, we bled the brakes. still had a soft pedal. so we bled the MC on the bench, and bled the brakes again. felt good to me, but still no brakes. after a week of bleeding we took it to a brake shop. the guy told us we did not have enough vacuum. I had hooked up the vacuum directly to the intake, thinking I would have full vacuum. I found a fitting on the intake with a rubber cap, so I assumed this was a vacuum port. Now I am thinking this was a temperature port or something. am I correct? could this 383 with a moderate sized cam have a vacuum issue I do not know about or am i just not hooked up to the correct vacuum port. It has a demon carb so I am guessing the rear port on the passenger side is constant vacuum?