MSD Installation

[johnboy151]

Greetings!
I'm stumped with some issues I am having after an MSD ignition install. My car is a 1974 Carrera with CIS. It's been sitting for about a year because I had no spark and no time to work on it. About a month ago I decided to replace the ignition with an MSD unit. I installed an MSD 6ALN, MSD 8222 coil and a tach adapter. I also installed a new Optima battery, New wires, plugs , cap, rotor, points, fuel filter and accumulator. I also drained the tank of the "thinner" that had been sitting there for quite some time. The car fires right up and runs pretty good above 3000 rpm. At lower rpms it misses horribly and will eventually die and will not start again for a day or two. It also smells as if I dumped a half gallon of gas on the floor. I pulled the plugs to see that number 2, 4, and 6 are wet compared to the others. I'm assuming that they are gas foulded and fear a hydrolock if I keep trying to start the car. I've triple checked all my connections and everything seems to be in order. Any ideas on what my next steps should be?

Thanks in advance

[Walter_Middie]

Sounds like a very large vacuum leak. It may be running OK at higher RPM because the vacuum leak is a relatively small amount of the total air going into the system. But below 3000 RPM a vacuum leak can be a large part of the air, and it's just running too lean.

Do you have a pop-off valve? Could it be loose? Are any vacuum lines disconnected?

Maybe a picture or two of your engine will help with some diagnosis.