The ZZ4 chip has more aggressive timing advance and fueling curves and less aggressive spark knock retard. Overall, its a hotter tune.
SBC powered 1987 Regal with TES headers, ZZ4 intake, ZZ4 PROM chip, mini starter, THM2004R, 2500 stall converter, 2040 cam, CCC system, and 3.73 posi rear.
2008 ex NPS P71 Crown Victoria, cop motor, cop shocks, cop brakes, and Jmod.
Never argue with an idiot.
They will just drag you down to their level and beat you with experience.