Stang Spanker

So as soon as I got my headers and ory my gas mileage went down like, 20%.
Is that normal? I thought my MPG would actually go up because of less obstruction.

Killaz

added bad a$$ sound=more foot on the gas=less MPG.

same happend to me.

CrippleFightin

Driving normally, my gas mileage improved by about 1 mpg. but as stated above, I drive like a bat outta hell so my MPG sucks.

87camracer

being as though you have ls1, you also might need to tune it. i know some buddies have installed long tubes and an ORY and picked up another 20rwhp after tuning. you might be running rich and must get tuned. something to look into if you havent.