I do not understand why the exhaust mod will not increase mpg. The engine would breath better, even without a cai. The 4.6 in my stx is weak compared to the 5.4. If I increase power and torque with the exhaust mod, and can keep my foot out of it, shouldn't the power increase cause my engine to work easier?
I do run a higher octane gas and that makes a difference in mileage and power.
But I do not want to spend up to $1k for no more return than a louder exhaust.
Help me out with your opinions please

 

I gained about 2 mpg when i put on my cherry bomb 2 weeks ago. or at least my truck is reading that i did.

 

You're only talking about a minor HP bump (esp if everything else is still stock). It may increase mileage, but it'll be so small that it's probably not going to be noticeable.

 

right nothing major or noticeable but the thread is simply titled WILL NOT increase mpg. i am just putting in my $.02 that there was an increase on my truck

 

And I'm agreeing with you. I'm guessing the reason that someone has told him it doesn't help is that often the gains are very small.

 

touche

 

Only if you're tuned for it.

 

When I put headers and duals on my last vehicle I got such a sweet sound that any mileage increase was negated because I wanted to hear the sound of the exhaust. So obviously the mileage got worse. I am running 91 octane and mileage has gone up from the 87 octane (with ethanol).
I will keep the airflow sensor clean and use the higher octane.

 

go pedal + exhaust = aural sex which in turn = loss of mpg + big goofy grin