# do ITB's lower fuel economy?



## docterelliott (Sep 29, 2007)

just curious if anybody noticed a difference in fuel economy after installing ITB's.


----------



## psychobandito (Sep 10, 2009)

ITBs will usually cause massive mileage drop do to heavy foot and audible extasy syndrome.

serious note, depends on what you're switching from. for the most part, the ability to tune them to perfection with a stand-alone will usually help you pick up a few mpg.


----------



## wantacad (Apr 4, 2003)

^ head on the nail there. if you drive it normal you'll pick up a few MPG with whatever fueling system you switch too. but your right foot and your ears will help decrease your MPG's. :laugh:


----------



## antichristonwheels (Jun 14, 2001)

itbs are not installed to increase mileage


----------



## docterelliott (Sep 29, 2007)

thanks for the input. my plan was to run a stock 16v with an autotech cam, nothing too crazy, and megasquirt. then my plans changed when i was offered some itb's for a deal. so itb's, cams, and megasqirt...would the itbs really effect the mpg that much with this setup? how do itb's cause a drop in fuel economy?


----------



## ps2375 (Aug 13, 2003)

It's all a matter of how much air you move thru the motor. ITB's tend to improve how much air a motor can "process", more air means more fuel, which means poor economy. But, as they also improve power, there is the possibility that economy can improve, IF the driver can control their right foot. The formula also works as: less air, means less fuel which means better economy.

Tuning the ITB's will be your challenging part, especially if you are worried about economy.


----------



## docterelliott (Sep 29, 2007)

yes but its not like air being pumped in by a turbo and thus would not need as much fuel as a turbo setup would right? therefore would have better gas mileage than a turbo setup right? my 2.0 8v turbo was getting about 20 mpg which is one of the reasons i decided to go with a close to stock 16v. i didnt think the itb's would make a huge difference besides sounding better.


----------



## Prof315 (Jan 5, 2009)

docterelliott said:


> yes but its not like air being pumped in by a turbo and thus would not need as much fuel as a turbo setup would right? therefore would have better gas mileage than a turbo setup right? my 2.0 8v turbo was getting about 20 mpg which is one of the reasons i decided to go with a close to stock 16v. i didnt think the itb's would make a huge difference besides sounding better.


A well tuned turbo set up should get MUCH better than 20mpg unless you are always very heavy on the gas pedal. I run my 20/20 fairly hard but I still average mid to high 20's driving daily and low to mid 30's on road trips/ highway driving.


----------



## ps2375 (Aug 13, 2003)

I think the biggest variable is how it is driven. With a turbo, how often you get and stay in boost will determine how good/bad the fuel economy takes a hit. It'll def be the same with ITB's.


----------



## docterelliott (Sep 29, 2007)

yah makes sense. anybody happen to know somebody running itb's and what mpg they average?


----------



## -RalleyTuned- (Nov 17, 2008)

I was getting high 20's in my rabbit when I had the gixxer throttles years ago, I think I averaged around 25 at the time. Was a b*tch to tune though so I gave up after messing with them for so long and switched to a really nice single TB intake, and then got 38mpg...:laugh:


----------



## need_a_VR6 (May 19, 1999)

I know when Mendra dailyd his mk3 he got 30+ hwy.


----------



## woodrowstar (Jun 17, 2005)

antichristonwheels said:


> itbs are not installed to increase mileage





ps2375 said:


> Tuning the ITB's will be your challenging part, especially if you are worried about economy.





docterelliott said:


> yes but its not like air being pumped in by a turbo and thus would not need as much fuel as a turbo setup would right?





-RalleyTuned- said:


> I was getting high 20's in my rabbit when I had the gixxer throttles years ago, I think I averaged around 25 at the time. Was a b*tch to tune though so I gave up after messing with them for so long and switched to a really nice single TB intake, and then got 38mpg...:laugh:


Are these serious responses? A more efficient engine makes less economy ??? That make no sense at all.


----------



## docterelliott (Sep 29, 2007)

so we've done most of the fuel tuning but havent really dug deep into the timing yet and as of now i got over 300 miles on the first tank after completion and some of that was driving it hard with pedal to the floor occasionally. so id say thats pretty good for an itb setup we'll see what it gets after more tuning. thanks for the input:thumbup: 
and to rallytuned, that jump in fuel economy is crazy lol. ill probably do the same after i have fun with this for awhile:laugh:


----------



## -RalleyTuned- (Nov 17, 2008)

woodrowstar said:


> Are these serious responses? A more efficient engine makes less economy ??? That make no sense at all.


Absolutley 100% serious. I never stated that the engine was not capable of good fuel economy, just that it was such a pain that when I made the switch I saw a huge gain with very little tuning :beer: and also a good note was I lost nearly no throttle response, but i'm using a 75mm TB :laugh:


----------



## docterelliott (Sep 29, 2007)

off what a semi truck?! LOL


----------



## -RalleyTuned- (Nov 17, 2008)

upgrade for a mustang 5L :thumbup:


----------



## ValveCoverGasket (Mar 20, 2002)

docterelliott said:


> off what a semi truck?! LOL


(_most_) semi trucks dont have throttles


----------

