Quote Originally Posted by BADAZGTP View Post
I know the turbo doesn't take from the motor because it uses the exhaust,
Not true. It has to get its power from somewhere. It does take its power from the motor in the form of increased back pressure. The engine will now find it harder to exhaust the cylinders since the turbo is in the way.

In general though, the parasitic losses caused by the increased back pressure is usually less than the parasitic losses from a belt driven power adder.

Quote Originally Posted by BADAZGTP View Post
but by running the smaller pulleys on the s/c, with supporting mods of course, get about the same.
The smaller the pulley you put on there, the more parasitic loss you're creating.