Custom slip on (need confirmation of no power commander)

[Joel Goodson_imp]

I don't like any of the slip on options currently available. I'd like to fabricate my own flange/pipe and add a pretty standard reverse cone style muffler.

I've read some contradictory comments on here.

Basically, my question is this.... After I fabricate this, do I need any kind of tuning? I don't think a basic slip on will lean things out too much at all, but was hoping to get some solid info.