Im just curious as to the answer of this question.

Does turboing your car 8-10 psi dramatically increase your mpg if your cruising?

My friend supercharged his 350z automatic and hes getting 27+ mpg city which is amazing considering to all the other upgrades hes done to the car. He daily drives it and the car sounds sexy


Now I was wondering if you guys have seen an increase of gas mileage while cruising your turbo'd 350z. I know i'm not supposed to care about gas mileage but im just curious.

thanks!

 

I am seeing about 27-28 mpg mixed driving mainly because I leaned low load cells to 14.7 where the factory tune was richer.

 

its directly proportional to how much power you make more power = more fuel consumed if you constantly flog it then your going to use more fuel. figure 10 psi to be probably around 75% more fuel during WOT due to extra fuel for cooling for a "Safe" tune

 

Is this what it says on your gadge or have you tried calculating it? And has anyone else seen this type of increase? I mean I'm gettin 18-20mpg and I got brand new o2 sensor and no cats and 28 seems pretty damn good

 

Gauge was reading in the 30's while cruising but I didn't believe it so checked once after a refill and it was 27. I record mileage with every tank fill since I bought the car new in 2004 but I haven't actually run the numbers in a while. I'm on the road right now. If I can remember to do it when I get back home I'll calculate the numbers pre and post turbo and post the results.

 

Thank you much man I appreciate it, so you tuned your car after the turbo which helped with the mpg?

 

No prob. Don't get home for a week, though, so might forget. Yeah, the drivetrain was completely stock before the turbo. Only thing I replaced was the battery due to failure and the belts and fluids for routine maintenance.

 

Just my experience, but I used to own a turbo Maxima. Initially I put a Vortech on it, but then switched to a custom turbo. On both setups, I picked up probably 3-4mpg if I was just driving normally. Of course it I beat on it, I was looking at like 10mpg. The only thing I could figure out was that when driving normally, I was actually driving easier. The car had way more power so I didn't have to push it as hard. ie, before boost, I'd have to get on it to merge onto highways or pass someone and after boost, I could just ease into it. I couldn't figure out anything else that made sense. Sort of like that Top Gear episode where they got better mpg in an M3 vs. Prius at the track because the M3 was cruising along while the Prius was driven hard to keep up.

This was 12 years ago, so I was tuning w/ rising rate fpr's and original e-manage so I wasn't able to lean out the low end or anything like that.

 

My turbo 350z gets 45mpg then. . . the 350z computer doesn't know you put larger injectors in the car and thinks it's dumping less fuel into the engine. It definitely gets way less

 

Yea the gadge defiantly will read different than the actual gas mileage but have you ever manually calculated off a full tank?

 

Yea no probs, and when u were measuring your 27-28 mpg where u like stepping on the gas every now and then? Or just cruising and driving eco the whole tank?

 

sc is not going to increase your MPG. You added weight and load to the engine. The reason the gauge is seeing higher MPG is because of upgraded injector flow rate.

 

I had 2 eclipse's one was a n/t the other was turbod. The n/t got horrible gas mileage, I maybe got 70 miles with a 1/4 tank. My turbo gst I could get it to about 114 miles in a 1/4 tank if I was trying to save gas. normally averaged about 90miles because I enjoyed topping it out to much lol

 

I drive with the flow of traffic, maybe a tad faster. I spend most of the time in vacuum but I'll get into boost and unwind it when entering the highway or passing. Also the mileage after the turbo is going to include WOT pulls to collect data since I do all my tuning on the street. I must have just had a 1 time reading of 27 mpg or I'm just completely mistaken because I just called up my wife and had her randomly pick some values from the log and here it is:
12/12/04 17.6
12/24/04 21.1
3/7/05 22.61
6/13/07 17.3
5/18/09 18.5
8/16/11 18.2
7/11/11 19.5
10/12/12 21.4
4/1/13 21.2
3/3/13 20.4
5/13/13 turbo
6/27/13 18.9
8/20/13 23.2
9/1/13 21.1

So I think we can say that MPG is at least the same after the turbo, maybe slightly better. Adjustments to my tune have been an iterative process since the turbo and I haven't had that many tankfuls of gas in the car to see a trend. I tried leaning the AFR past stoich to 15.1 at the low load vacuum cells but the ECU doesn't seem to want to lean past 14.7.

 

I don't think i've even gone through a full tank with my z after I turbo'ed it. I barely drove it before the turbo(less than 3k a year) i've managed to get 35mpg before turbo with kinetix v+, test pipes, injen ses exhuast and injen intake. I drove about 45-50mph on the highway for 30 miles then had about 4 miles city at around 30mph and start to finish was 35mpg

 

45-50 on the highway?? What's your highways speed limit where you live?

 

Lol 65. I was just trying to see how good MPG I could actually get for that one ride. I usually drive my car like I stole it

 

Oh alright lmao. I was going to say I hope they're not 55 there lol. The highways around me are finally moving up to 75. Can't wait!

 

I am getting like 15mpg on my with mine being tt. 14.3-14.8 while cruising does this seem a little low to anyone? I do get on it but not my average for a tank to be that low.

 

What's your target and actual AFR while cruising? How often are you in boost?