Difference between a gen III and gen IV 6.0
you can then figure out the heads, intake, VVT & other factory options.
Please chime in if I have forgot something, but thats about all I can think of for now.

COMP - FAST - PACESETTER - WISECO PISTONS - LUNATI - CALLIES - NEW TSP BRAND CRANK & RODS - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - ARH HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - PRECISION INDUSTRIES - YANK - CIRCLE D - AND MORE!


