NooB Confuzed about boosting, help!

[titanium240]

This is probably the dumbest Noob question out there, please don't flame. I'm really new to turbos so I don't know exactly how they work, is there any way to "shut off" a turbo or stop it from boosting while driving and activate it when racing or when you "need" that extra power? I'm thinking about boosting an S13 but I don't want horrible gas mileage...wait, does gas mileage change when a car is turboed?

I'm getting the car mainly for the low gas mileage, so knowing this will help me figure out wether to keep it N/A or go turbo for more power.

Thanks for helping a poor confuzed NooB!

[AustinSilvia]

gas mileage could remain the same if you keep your boost level and power level low. once you reach anything above 7 psi or so you have to replace the fuel pump, up the injectors and do other fuel management modifications to compensate for all the extra air that will be in inside the cylinders. if you fail to up your fuel consumption and run a turbo with too much boost you will run into detonation. it is possible to run different settings on a digital boost controller and digital fuel control such as an safc or even a stand alone power fc or such. these kind of toys cost a whole lot of money though. it would be cheaper to set up one car for fun/racing/whatever and set up another cheapy car for a few grand as a daily driver. a power fc alone costs over $1000. getting someone to dyno tune it all and set everything up will cost more, and then you still won't get that good of gas mileage. my suggestion is this: get a 240sx for fun and then get a honda or a motorcycle for daily driving.

in any case whether NA or turboed the secret to power is fuel control. so no matter what if you have a fast car and lots of power chances are it'll get crappy gas mileage, unless it weighs nothing. see gas mileage is directly rated to power to weight ratio. for instance: my motorcycle is a fast son of a *****. it runs an 11 in the quarter mile, and it still gets 50+ mpg. but it also weighs 350 lbs, where a car weighs at least 2000 lbs in most cases (even the lightest hondas are 2000 lbs.) 240sx's weigh around 2800-3000 or so lbs,without people in them. so anyway whatever you choose, if you're gonna have a fast car you need to plan on spending money on fuel, and/or having a second car or mode of transportation for daily use. this way you get more life out of your fun car, plus you wont be spending loads on gas every day for a stupid commute to work or whatever. i think that pretty much covers it. by the way wont be embarassed to ask questions... that's what the forums are for. do use the search button though, because many times topics have been covered a million times over.

[DammitBobby]

I strongly recommend reading Corky Bell Maximum Boost and Building and Tuning High-Performance EFI by Ben Strader. It will answer a lot of questions.

[IvanAtSPRacing]

The only time you will be using more fuel is when your making boost.

The only time you will be making boost is when you are at WOT (or close to it) and your turbo is above the RPM needed for it to spool.

Drive it around keeping your foot off the throttle and your all good when it comes to gas milage.

[nissanfanatic]

Yep, that is the beauty of turbos. They only work when you want them too. Kinda like the engine itself.

[Structure240sx]

yep i get 300miles to a tank of gas easy off my car around town. and 350 if i do a lot of highway. i dont drive too fast on the streets just boost here and there. this was when i was boositng 13psi.

have the car tunned decently and you will be good to go