Tuner question
 

I just got my tuner today. I installed the 93 performance tune. My question is how much difference is the 93 perf. vs. the 93 economy?

wat kind of tuner did u get?

My bad. I installed this:
Steeda 2005+ Mustang GT Complete Cold Air Intake Kit and SCT X3 Combo

And also, if I install the Mustang SLP Power-Flo Axle-back Exhaust , will I need to retune, and will I get any additional power?

i dont know about the tuning 2005 mustang but for the 93 per. and 93 economy octane. i think there really isnt much difference or i could be wrong. Just might want to wait until sum1 else talks about it, But 93performance is for whenever u go to the drag strip and 93 economy is for whenever you are driving in streets. But like i said just wait until you hear sum other opinions.

My install
 

I just recently installed the same setup on my 07 and i am running it full time with the 93 octane performance tune and my gas mileage has stayed pretty good . Over about 800 miles (70% hiway - 30% city ) Im getting about 22 mpg

That is pretty much what I am getting. I am getting ready to add a GMS throttle body and magnaflow axleback exhaust. That will be about it for my MODs. I just wonder if, adding this horsepower affects the life of the engine heads and other internal motor parts?

Hard to say w/o knowing exactly what they did.

Chances are that the non perf tune has a degree or so of timing pulled. Maybe even a tad leaner so you burn less fuel for better mpg.