Question Concerning Engine Type And Roll Baretc...

[Bahamian]

I have a 2007 Hilux 2X4 truck that I have been the proud owner of for 1 month. I have a few questions I am hoping some people can answer. Firstly the truck came with a 2KD-FTV diesel engine and as I look in the owners manual I see there are 3 versions of this engine with different power outputs. I was wondering what are the differences between the 3 engines to make the diffenrent power numbers if itsa the same engine, is it just the programming on the fuel system or are there differences in actual internal components which I couldnt change myself to up the power so to speak? My second question is my truck came with a roll bar looking device but I believe this is more than likely there to protect the rear window from impact from objects in the truck bed and it has these little metal flaps at the top of the bar on either side. What are these flaps for? And the last question I have is I have 5 lug wheels is there a lift kit to raise my truck?