The June issue of Mod Mustangs & Fords has an article on pg 76 testing the results of some high voltage COPs on a 08 GT/CS with CAI and tune as the only listed mod. The results showed an increase of 27 HP on the dyno. I have seen several comments here that have said that these COPs only make a difference on an engine with power adders. I'd like to know if anybody else has experiences like with this kind of mod. $500.00 with 1 hour labor resulting in 27 HP increase is nothing to sneeze at. Thanks