will a 4-2-1 header hurt gas economy? i am curious about that

 

only if you put your foot into it

 

I think mine is about the same.I haven't calculated it,but it's definietely not worse.

 

Yup, if you get on it and stay on it you will have to fill up often. laugh.gif

 

mine went down with auto tranny

 

Your fuel economy won't be made worse by a header (i.e. putting a header on does not, by itself, make you car burn more fuel). It really depends upon how you drive. Most people see a decrease in fuel economy because the drive and accelerate faster after doing the mod.

 

post CAI, 4-2-1 headers, and catback exhaust- I lost mileage. (and I don't get on it... much......) :-)

 

good to know

 

its the cai that did it to you. it allows more air to flow in, the computer sees that and then adds more fuel. none of the exhaust components will decrease your gas mileage.

 

it's completely opposive on XD, but we have MAP sensor, so when you add CAI your FE will go up smile.gif