Intake and gas mileage?

[HotSnatch]

An aftermarket intake will increase the airflow to the engine, thus more fuel is injected into the cylinders to keep the air/fuel ratio the same. Great, now how much will this affect my gas mileage?

I would assume that gas mileage is pretty much unaffected unless you put your foot into and you're at high boost. In which case you will have slightly worse gas mileage because you are making slightly more power. Is this a correct assumption?

Sorry in advance if this is a really retarded question.

 

[MS3Pilot]

I've had my intake on now for 5 days, and my mpg has gone down a bit. I attribute this to my getting on the gas a lot, because I just love the sound of it. However, under the same driving as the stock intake, I would expect there to be a slight, possibly negligible increase in fuel economy due to a reduction in pumping losses.

my .02

 

[Wurf]

If driven the same way before and after the intake is installed, there should be no reason for the mileage to change. The only purpose of the aftermarket intake is to allow the motor to ingest more air than it did previously, and this will only happen at the point the OEM intake was restricting the motor. When is your stock intake restricting your HP output? That would be shortly after the motor starts to make boost, and I base that on the dyno graphs I've seen for the various aftermarket intakes comparing them to stock.

You might be thinking of the old adage that a dirty and therefore restrictive air filter lowers your mileage. This does not apply to fuel injected cars with a mass air flow system. You simply loose HP as it is measuring the flow of incoming air and pulsing the injectors accordingly.

 

[lanny709]

True. Whether a SRI or CAI there should be an increase in gas mileage as long as it is driven normally. However, it's like a bug. When most people hear the booming sound that the intake makes for some reason it causes their foot to go to the floor everytime they step in the vehicle. So, overall an aftermarket intake is slightly contradictory for most... Unless you don't mind sounding badass and spending more money on fuel

 

[HotSnatch]

I think the verdict is I should get an Intake. haha. If only the mazdaspeed cai wasn't like 350 bucks...I wanna go straight for the cobb sri, but I don't wanna mess with the warranty. Gotta ponder about this one for a bit.

 

[khoney]

Got my best mileage ever on the last tankful after having the Cobb SRI for a couple of weeks now. 26.4MPG! That's more than 10% over my typical.

 

[lanny709]

SRI is the safe bet and the best part is that for warranty purposes it can be easily removed! DOOOO ITTTTTT

 

[coyfish]

Yeah intakes would give you a small mpg gain if anything.

 

[steven88]

the stock airbox is the biggest POS ever...not for all cars...just for the MS3

if you look at it, there is a SMALL ass opening to feed the air through...and its not even connected to the fender well for cold air...its just a small hole right there...VERY restrictive....camrys and accords use an airbox but it is well designed because theres a snorkle that feeds COLD air right from the fender well....this is a good designed airbox

you will see nice gains with the intake on the MS3...you won't regret it