Hey guys I need a little help, I am going to buy a 2007 new style 1500 with the vortec 6.0L Variable Vaule Timing v8 SFI it says it is rated at 367hp and 375 torque. My question is, is this engine any different from the one that comes in the silverado ss or is it more powerfull or is it the same exact engine. Also is it High output and what is the difference between SFI and MFI. I would like a SS but I need the crew cab what do you guys think?