for the safely modding your 3800 can that be used with newer models as well?
In general the 04+ GenV cars can not run as small of a pulley as the 97-03 Gen3 cars with the same modifications due to the GenV being more efficient and making more power out of the box.
Dont do it. I ordered the Stage 4 Heads and Cam package from Intense a month or so ago. Sent it all back for ZZP CNC Heads and XPZ build. Hell the 899 CNC heads are completely and i mean every nook and cranny clean. The IS4 Heads had grime still caked in corners and spray painted over. Hell in the drop down for the package I selected Rollmaster Double Roller and received a JP set. They sent a damn GM Timing Chain Damfener when i was going to be doing a Double Roller. Dont Do it. Just take my little experience and go about a better route. Hell get some heads ported cheap off the forum or take your heads in to be ported for half the price and go with say an IS2 or IS3 cam or XPZ or damn custom grind. Its all what u prefer.
INTENSE Heads and Cam Package dont save u money
EVERYTHING IS THE SAME...minus the pulley drop and the tuning...you have to get a 04-05 PCM to tune your car otherwise the gas gauge will read in reverse.
As for the pulley drop it is nothing but running a little larger of a pulley because of the Gen V vs. the Gen III...look at it like this...since the Gen V is more efficient than the Gen III, you don't need as much boost to make as much power...therefore it creates less heat and is less parasitic than a Gen III.
3.4" on a Gen III = 3.6" on a Gen V
3.2" on a Gen III = 3.4" on a Gen V
Follow? Everything about our cars are the same really minus those two things...