Would a slight exhaust leak make me lose power. It's leaking between the flange that bolts to the jug and where the pipe slips over it(where the spring is). It's a fmf fatty. Is anybody else having problems like this?

 

I had a slight leak same place on my Blaster, different pipe. Go to an auto parts store and buy some exhaust pipe sealant by Permatex. A light film of this solves your problem

 

Mostly all aftermarket pipes do this on the blaster. You can use exhaust cement or other high heat seleant to make it stop. I don't think it would affect the power output at all, just makes a mess.