Thread: MPG??? B chassis

With the gearing in the Sentra trans I can see that. Though even on the P11 going 75mph rendered me 3-4mpg less then 70.

Always have been using arco gas but recently I advanced my timing and side gapped my plugs and started getting terrible mpg's... I filled up with costco gas and it went from 20 to 25.. I've been leaving late for work lately so I've been having to drive fast (constantly from 65-100, back and forth going through 3rd and 4th) and got 18 when I tried arco again... Now that I'm on costco gas again I can already see the difference... Drive like crap + get 25mpg, not baddd

i Don't understand how the heck you guys are getting 30-35+ mpg in your sentra?? Wiki says our cars are supposed to be doing 21 MPG city/29 MPG highway

Nissan Sentra - Wikipedia, the free encyclopedia


Maybe its where we live..??? I drive about 90% City and 10% Highway. Houston, TX. The most i've seen on 1 tank, driving about 90% HWY and 10% City was 260 miles to the tank which is about 26mpg on a 10gal Fill up, which is what we b13 owners normally put to fill up if we're on empty.

I got 33mpg on my bone stock 99 SE-L (heaviest of all B14's).

Now the reason the numbers are so low is because the government changed how it measures the MPG's in the last 4 years. By new MPG testing methods cars got about 10% less gas mileage then previously, thus they assumed all older cars would get less gas mileage and just updated the numbers to be less.

Now Another thing to keep in mind is Ethanol, ethanol hurt my gas mileage by about 2-3mpg.

Even with Ethanol, I was able to get 35mpg on my turbo P11, but that was a hard one to keep (going 70mph).

Well mine seems to be about right with what they say.. At the very least i'm getting 20mpg, which fluctuates to about 26mpg.

Would a nismo thermostat cause the car to run a bit richer?

Only if it's overcooling and not getting up to proper temperature. A thermostat alone shouldnt do that.

I started to drive my B14 again and I've noticed my car is dumping a ton of fuel. I followed Andreas' advice and just ordered an AFPR to set my fuel pressure right. Hopefully this will cure my low MPG woes. It's sad to get around 20-25 mpg Highway when only a few years ago I averaged 37+MPG on one of my trips to Texas.

Yup it would. Nismo thermostat is what 130*F? That means your motor starts cooling itself down while it's still warming up. There are OEM enrichment tables to 160*F, so if your water temp stays below 160*F you will be seeing more fuel dumped.

I have a stock OEM thermostat, which is 170*F, my with my Koyo radiator on the highway I don't really get above 180*F, which I'm pretty sure is why I'm only getting 28mpg now NA (I got 35mpg with stock radiator).




Ethanol + old gas?

Youve got to take into account also that those are stock numbers. Once you start putting bolt ons on and freeing up power it takes less fuel to make the same power thus using less gas. My bolt on 91 se-r back in 03 and 04 would average about 28-30 with mixed intown and highway driving, Highway only going from Texas to Az I got 34-35 mpg easy.

My current se-r with 450whp on pump gas was getting me 32-34mpg with mixed driving going to work and that included getting on it several times on the way to and from work. On the highway only going to the track without getting on it i got 40 mpg even. Pretty freakin good. Its all in the tune. Stock tunes are very very conservative.

My buddies VE'd, n1 cam, n1 manifold, calum realtime I tuned his car and he was getting a best of about 42 mpg on the highway going from yuma to tucson every weekend. He would get 32-35 with mixed driving and of course occasional spirited driving. All in the tune. Seriously.

I wish i would have had the time to spend fine tuning the partial throttle and cruising a/f ratio after i put the 6 speed in, 1000 rpm less on the highway would have made a huge difference once i tuned it out, put more timing in and took away some fuel at cruising rpm and load. Probably could have darn well saw close to 50 mpg pretty easily.

My DET B13 gets about 20-24 avg (but thats because I drive it hard)

The most I got last summer on a drive back from SC, was 28mpg

Still collecting stuff for a 6 speed swap...