MiSo

exhaust is actually bad for your gas mileage.
it makes you lose tq thus making you get on the gas a little bit more just to accelerate the same. *exhaust is beneficial for higher rpms though.. but thats a different story and gets a little more complicated when trying to match up engine size vs. exhaust size(diameter)


just dont accelerate that quickly.. and use cruise control when you can.

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i have a apexi safcII in my car.. which is a air-fuel converter (optimizes mix for better performance), but also monitors things like revs, throttle, air, and knock.

during normal acceleation from a stop, you waste alot of gas. this is where most gas is wasted.... stop and go. so try to accelerate slowly.

also use cruise control. if im going 70 mph and use cruise, its about 12% throttle to maintain that speed. if i try to maintain the speed without cruise control i'm seeing about 18% throttle. so thats an extra 6% thats being wasted. whenever possible, use cruise control. it helps with gas mileage alot.