PAC Racing PAC-1280X-16 Valve Spring Set 604 Crate engine cheater springs February 13, 2024 Comments Off Posted in: racing This is Pac Racings “604” crate engine “cheater” spring, a must have for your crate program, will pass tech. Share Tags: cheater, crate, engine, pac-1280x-16, racing, spring, springs, valve Comments are closed.