Do I need a new mechanic?

I dropped off some parts for him to install, as I am wqay to busy to put them onmyself right now, and would like to get in some fun before the winter hits up here.

I had some oil leaks around my intake manifold near the dizzy, so it had to come off anyway I decided that the intake I had (Weiand 8007) needed to go, it needed a heli coil., and had the smaller intake runners. I upgraded(?) to the edelbrock rpm airgap. I figured with the larger ports, I might lose a bit of velocity, so I added a holley 4 hole carb spacer to try and keep the speed up.

Did I make a mistake? My mechanic thinks I will loose all my bottom end with this intake and Spacer? I thought I had done my research? What do you guys think?
Author: admin