NA or boost , MPG?

[cabdisaster]

ok so i have been thinking about the milzy stage 2 kit and the injecter conversion. i would assume with more fuel going in and a larger lift that gas milage would go down alot, i get on avg 300 miles to a tank and im happy with that. this one kid i knew had a turbo'd sentra and said his gas milage was just as good as a stock sentra and that it all depends on tuning.

so my question is, which is the better one if i dont want my mpg to suffer severely? id rather do NA but boost seems better in the long run

[Bjornboy81]

It really depends on how you drive it. Usually with all the extra power you'll get on it more often and that will kill you gas milage. But, with the extra power avalible, you engine is now more effecient so you should get better milage if driving it easy.

It also depends on the type of driving...in city driving your milage will go down with performance mods, but on the highway, it should go up. :)

[coupe]

You want to do these big mods and your worried about MPG?

[Matt95GT]

It depends on tuning. When using larger injectors, improper tuning cause a huge drop in fuel economy (due to overly rich idle). If adjustments are made to compensate (PCM), and closed-loop idle functions properly, fuel economy should be similar.

My fuel system is all hacked from stock... once I got it adjusted right, my gas mileage is pretty much the same as what I got pre-supercharger. It's just hard staying off the fun pedal.

Off-topic... which engine did your friend turbo in his Sentra?


Originally posted by coupe
You want to do these big mods and your worried about MPG?

Yes, that's also something to consider. Similar to those concerned about having to run premium fuel for boost or advanced ignition timing on NA.

[xtremecold]

Your highway MPG should stay the same, somewhere in the ballpark of 30 mpg. But your city mpg will suffer a bit. For doing the NA that is, not sure about boost.

[cabdisaster]

Originally posted by coupe
You want to do these big mods and your worried about MPG?


i think mpg is something to consider when doing anything that will be affecting the car for the rest of the time i own it, yes it will cost alot to do these things but if it would cut my fuel economy in half then its going to cost me 80 bucks instead of 40 a week or id have to drive half as much so yes i am worried about mpg.

i cant remember what engine he had in it , it was a twin cam but i cant remember much about it, it may have been swapped from another nissan maybe a v-spec ? im not too familiar with nissan

[Bjornboy81]

Originally posted by cabdisaster
i think mpg is something to consider when doing anything that will be affecting the car for the rest of the time i own it, yes it will cost alot to do these things but if it would cut my fuel economy in half then its going to cost me 80 bucks instead of 40 a week or id have to drive half as much so yes i am worried about mpg. I agree...just because you want power doesn't mean you're willing to give up decent milage to get it...a small loss, sure, it's enevitable, but not a huge loss. :)

[Themeneea]

with a proper tune you would be fine. its not like your boosting at 2000prm

[cabdisaster]

thanks every body for there input.

[TA^Guy]

What it boils down to is volumeteric effecency and drivng normally.

A forced induction motor, even low boost, typically has more effect fuel consumption due to a more compete burn rate and higher volumeteric effecency compaired to a simular naturally asperated motor.

The higher cylinder pressure allows faster, more compete burn of the the fuel mixture with in the cylinder resulting in more power with less wasted fuel. The main reason why a forced inducted motors can make more power than a simular naturally asperated motors. A finely tuned forced inducted motor driven lightly can easily make better fuel effecency than a NA motor.

The big problem with fuel effeceny in a forced inducted motor is when people want more power. Obviously since fuel is the stored energy you simply can not make more power without more fuel. Now, the desire for more power effects your fuel effeceny. Not to mention when you want to make use of all this stored power, you plant your foo ton the go pedal to get the rush and fuel consumption is incressed.

My 1984 Buick Grand National with a lightly modded 3.8 Turbo would get as good or better fuel ecconomy than my '01 S10 Xtrme does. Yes there are alot of varibales but many as simular. Both have sequential fuel injection, both are V6 engines mated to a 4 speed automatic with overdrive and a limited slip and the same gear ratio, even vehicle weight is simular. Only big difference is that my Grand National made a great deal more power and torque than my S10 does.

So basically, with a forced inducted motor with mild boost and fuel mapping you can get just as good if no tbetter fuel ecconomy when driven maturely.

I hope this helps answer your question as opposed to other's typical useless posts and battery.

[Colin]

So basically, with a forced inducted motor with mild boost and fuel mapping you can get just as good if not better fuel ecconomy when driven maturely. Kind of like how i drive ....
:old:

[BigRandCarFan_5]

If you go NA, you mpg should go up in both city and highway. While generally from what I've seen, boosted engines usually go down in the city.

[TA^Guy]

Originally posted by BigRandCarFan_5
If you go NA, you mpg should go up in both city and highway. While generally from what I've seen, boosted engines usually go down in the city.

Funny because my 20 year old slightly modded turbocharged engine had better fuel ecconomy than my 4 yearold naturally asperated engine with less power.

Driving conservitivly plays a huge role in estimating fuel consumption.

[tejohnson]

For forced induction, depending on the turbo used, you will actually see pretty good milage. As for around town, as stated above, it depends on your driving habits, what injectors you go with, and how you tune the PCM...

[dangerranger]

Just curious, what kind of fuel economy do you guys with 3400 GTs get? Is say, 24mpg really bad?

[Colin]

Originally posted by dangerranger
Just curious, what kind of fuel economy do you guys with 3400 GTs get? Is say, 24mpg really bad? Depends , in the city that's good , on the hwy should be around 29 - 30 mpg average ...http://www.gaownersclub.com/forum/showthread.php?s=&threadid=50449&highlight=gas+mileage