Have some mods planned that brings a question to mind on tuning. I see the set packages on line that are straight forward enough. But if you do something different, where does that leave you for tunes.

I have a Cosworth drop in now, and am planning on a 3" Cat back, most likely the Sakura street. So what tune would I use with a Cobb AP3. The stage 1 as example would probably handle the drop in, but what of the exhaust.

Regards,
Kevin