Check out this monster 630 RWHP ZL1 by Late Model Racecraft (LMR)! And who doubted the ZL1 could be tuned 
Modification list features:
LS3 Comp Cam Kit, Comp Custom Grind Cam Shaft,
Comp Double Valve Spring kit good for .675 lift,
Titanium Retainers, Spring Seats, Valve Seals, and
Comp Chromoly Pushrods
LMR Custom Torque LMR Custom Torque Converter
Upgraded Heat Exchanger
Solid isolator
2.55″ upper pulley
Upper pulley hardware kit
Dowel pin
Pulley cap
See rest of mods list INSIDE…
See the full build details and a video at the following LINK
