Recently I have been having a problem with a miss in the ignition of my 280 C. I had replaced plugs, wires, cap, rotor, and coil. I had checked the dwell, timing, and vacuum but had not been able to eliminate the problem. Being an old racer I decided to install a Jacobs I.C.E. ignition system on the car. The new ignition has totally solved the problem. I don't know if the problem was in the spark control box or what. With the new ignition system the car is alot more responsive and I have gained 2 m.p.g. When ordering one you need to indicate you need bosch style wire ends on the wire from their coil to the dist. cap, they sent me the wrong one. They also recommend replacing the platinum plugs with copper, because their system works better with a higher resistance plug. I have my plug gap set at .049" and the plug color looks fine.