Brian Tooley BTR Stage 4 NA Cam - LS1 LS2 LS6 5.3 5.7 6.0 233/248 .630"/.615" 111.5LSA 3-Bolt Pattern Great camshaft for LS1/LS2 applications where a really rough idle is desired with more top end power than the stage 3 cam. This camshaft is very aggressive for a daily driver application. With 16 degrees of overlap it has a rowdy sounding idle, and makes great top end power at the sacrifice of some low end torque. Automatics will require a 3200rpm+ stall converter. VVT engines will require a VVT delete kit If installing in an engine originally equipped with a 1-bolt camshaft, a 3-bolt conversion kit will be required.