Many Street Stock racing classes limit the ignition to stock-style replacement parts. For most Chevrolet and Ford engines, this means an HEI distributor is the only option.

Restoring Power To A Damaged Mallory HEI Is Easier Than You May Think - Circle Track Magazine ...

Corvettes have had electronic ignition systems for over 40 years, starting with the powerful, dependable Delco HEI (high energy ignition) system in 1975 models.

The HEI distributor is still an inductive-discharge ignition, but exchanges points for an electronic device called a module.