Intense Stage 3 includes:
Intense modular pulley system which uses a 2.9" pulley,
Oversized tensioner pulley to prevent belt slippage or can use GM stage 2 belt,Autolite copper core plugs,Lucas 42.5lb/h fuel injectors,Casper LSJ injector wiring harness, and Intense Stage 3 PCM and tune.
I have stage 4 which is the same but uses 60lb injectors and a 2.7" pulley. I put down 261.5 hp and 243.4 tq. I highly recommend the Intense kits if you don't mind voiding your warrenty. Although the Intense kits can be reverted back to stock if warrenty work is needed.
GM Stage 3 includes:
76mm pulley, 2-pass intercooler end plate, and custom tune for smaller pulley, adjustable rev limiter, 100 octane mode, and set up for 50 shot of nitrous. It is also an " off-road " kit