If you choose the HEI ignition option, look for a unit with a vacuum advance and a 4-pin module. The ESC distributors with 5 or 7 pin modules must also have a computer, and the 5-pin ones are notorious for failing quickly. If there's a 4-pin oval connector attached to the HEI housing, with or without a vacuum advance, it's not a stand-alone unit. There's also a way to make the HEI reliable up to about 7K RPM or so, where the standard units start to spark-scatter at around 5500. That's another sneaky trick we used that my competitors in the "stock" round track class couldn't figure out. We always ran our engines 1,000-1,500 RPM faster than all our competitors, and the tech inspectors couldn't catch us.
Jerry
