If your not looking to race your car and just wanted to get the benefit of little more hp/torque and better mileage, is it possible with either? I just drive highway 85% and city 15%.

 

As with any mod, I think you can maintain a good MPG if you dont stomp the gas. I on the other hand have a lead foot so my MPG are gonna go way down. But good MPG with a SC and a turbo have been proven.

 

If you go FI, your going to lose mpg...PERIOD. No matter how you drive, you will need the extra fuel to go with the extra air. Realisticly, expect mid 20s mpg if you go S/C or T/C. You can go with an extremely large turbo and have no boost in the low end but then your engine will lose efficiency as some of the exhaust gases will have to go to the T/C

 

I just can't off the boost. My rs1 with the greddy blower gets about 18 but its lots of fun.

 

Doesn't turbocharging (with an efficient turbine) generally add fuel efficiency by increasing low end power?

 

Youll have to be the judge of that. If your goal is to be power efficient, youll have to see whether the 9-10mpg trade off is good for the power gained. THEN you can see if it is efficient for you or not. Its simple mathematics, turbo or supercharge equals more air in the motor right? With more air, wouldnt you need more fuel regardless of how much power you are making? If you go FI and you are not burning anymore fuel then youre running lean.....= BAD. Efficiency is the balance of power, economy, reliability. Its not only mpg. I hope this helps.

 

Over the weekend I did alot of driving mostly on the freeway and my mpg was 27. This was just a straight up miles divided by gallons put in. I guess since my greddy turbo is a little smaller than the TD04 I used to have plus since my current setup is more efficient IMO, I am getting better fuel economy than I did with my old turbo setup...not by much, but a little. Typically I get about 25-26 in mixed city/highway.

Oh yeah, the above, was with my car loaded to the max. Meaning, I had 1 other adult with me and 3 pretty much grown teenagers with the back loaded with camping gear.

 

Ultimately, I'm thinking about using a small turbo, boosting low enough to get extra hp and torque but not waste gas. Secondly, As much weight reduction as possible, Carbon hood, trunk, mirrors, fenders, bottom lip, Motegi 17 track lites, Recaro Racing Seats. And hopefully I will be getting better gas milage plus a little extra, OOOOhmpfff.

 

cutting the fat will help alot on it's own.

adding the diet and a moderate F/I system with resonable throttle usage together could result in a few mpg increase. the trade off though is going to be cost to get there vs. the few mpg increase won't really be putting you ahead $$ wise. now if you are just looking for an excuse then you are excused

however most folks i know that have boosted anything get the bug and can't/won't stay out of it.

 

Thats because the surge in power that comes from a turbocharged engine is just super fun. Youre not going to get the same power delivery in an NA engine. A sudden surge in power means your powerband is pretty much out of wack (imo) but its still a great feeling.