Includes drawings. The $6 GM Engine Trick That Woke Dead V8s Into Monsters!
Engineers knew about it but would not admit anything once emission controls were certified.
Racers knew it, but didn't want to give away a tuning trick to their competition.
Muscle Car Masters
29.1K subscribers
58,270 views Premiered Dec 22, 2025
In the late 1960s, small-block Chevy engines weren’t losing power — they were losing control. After heat soak, airflow broke down, fuel separated, and engines turned inconsistent. While GM focused on calibration and emissions, street racers quietly discovered a six-dollar carb spacer that fixed what cam swaps couldn’t.
By changing distance, plenum volume, and heat transfer, the spacer stabilized mixture behavior under real conditions. From Smokey Yunick’s experiments to NASCAR banning tapered designs, this is the story of "The INSANE $6 GM Engine Trick That Turned Slow V8s Into Monsters" that GM never wanted to explain.