gas milage after catback install?

[wickedh3]

stock under the hood also.

I own my own shop building mustangs and tuning them in NJ. so im very familiar with the ecm stand point. I have a call into diablo to see if theres something that could be going on in the drive by wire tables due to the increase in torque.

I know the reasons for an exhaust to zap fuel, but if you drive "softer" the milage should come back, unless the ecm isnt allowing it.

Anytime you increase torque production at a given rpm fuel requirements go up. So i know thats where the intial fuel lose went...but easier driving should allow it to get back to that area.

All i know is my girl is bummed that her 17-18 is now 15-16. The truck feels great and def has alot more ummpfff, but at a cost of fuel like this? i dunno if its worth it.