This GM HEI has the typical gummed-up mechanical-advance mechanism. Note the corrosion on the advance-weight pivot pins (arrows) caused by voltage arc-over and lack of lubrication. Brad Urban at The ...

Ignition timing is easily the single most important tuning adjustment on an internal combustion engine and yet the concept of ignition curves continues to be elusive for many enthusiasts. Yet all it ...

When General Motors introduced the High Energy Ignition (HEI) distributor in the mid-1970s, it was revolutionary. So much so that it still has a strong following among today's hot rodders. Like other ...

High performance is all about horsepower. But even the ultimate in heads, compression, cam, and the rest won’t make power if you can’t light the fire. Ignition systems don’t make horsepower, but a ...

Having a car with outrageous low-end throttle response and top-end horsepower is something every gearhead strives for. The correct combination of parts will get you close, but it’s the tune-up that ...