Precise ignition timing is essential for high-performance engine tuning and ensuring your small-block or big-block is delivering every horsepower within its capability. Since the era of poodle skirts, ...

Precise ignition timing is essential for high-performance engine tuning and ensuring your small-block or big-block is delivering every horsepower within its capability. Since the era of poodle skirts, ...

Building Big BirdTom 455bird via CarCraft.com: I just bought a Pontiac 455 for my '68 Firebird. The car has its original 350, and I'm hoping to slip in the 455. I read "Junker to Thumper" in the June ...

Editor's Note: Way back in March of 1998, GMHTP ran "Opti-Spark" by Ray Bohacz, an engineering-level dissection of GM's Opti-Spark distributor. This evolutionary ignition component was a bridge ...