I have a 1966 Toronado. I have rebuilt the carb and the car idles well and sounds great when it revs up, but when I put it into drive the car dies out. Kind of like when you turn down the idle to low. I have put a new vacuum line from the master cylinder to the top of the intake manifold. This appeared to help some, but the car still chugs and dies out in drive. Someone at some point has put a jegs power booster and dual master cylinder on here. They also put a performance adjustable proportioning valve with prop block and di; and they replaced the front drums with rotars. I was wondering if this system could be messing up the vacuum. One other thing. The car had bad gas with a little rust in the tank. I drained it out and used seafoam and put about 10 gallons of premium gas in. I did not change the fuel filter. I am not even sure where it is. I would think if it was a gas problem it would not run good in idle. Anyways. Any information would be great. This car is starting to give me a headache.