Your MPG/Highway Cruising Speed?

[BpuVR4]

Wanted to see what speed/rpm you guys cruise at on the highway, and in reference to mpg.

I cruise 65pm @~3k rpm and get a mixed 20pmg trying to stay out of boost as much as possible on the highway. 205/60/16 tires & E3 16G.

 

[JamesFoster]

I get about 20 on the highway iirc, I have the EvoIII taller 5th in my trans, and I cruise at 75-80 usually, I think right around 3k-3200 rpm. 235/45/17 tires, E85, 2.3L with a big turbo n' stuff. I average around 15-18mpg with mixed... Shall we say rather agressive driving and cruising.

 

[coyotes]

I have got 30-32 super mellow driving at 60mph here in seattle. My last tank I only got 18, but I have been ripping on the car pretty good since I got it back together.

16g, stock boost, fmic, turboback. Winter tires

 

[turbohf]

i was getting solid 17mpg... but i have been fixing sh*t, buddy tweaked my MAFT, and i got 22.5mpg on the last tank. thats with some stop/go north seattle traffic. mostly out of boost as i melted/blew up a coupler off the turbo again. if im cruising on the freeway 65-70mph.

2.4L, fp2 cams, fpred turbo, all other supporting mods (and broken aem box, hence maft)...

 

[turbowop]

During the fuel mileage test at IMSCC last year I was able to get 34mpg on an 80 mile drive. But I was babying the sh*t out of the car.

During a normal drive to Seattle from Yakima I see about 28mpg. But that's also about 135 miles and over a mountain pass. Normal speeds on such a drive are between 75-80mph.

 

[tektic]

I have not driven my Galant enough to test. Not entirely relate but my 1990 eclipse gsx got a pretty consistent 26mpg highway. It's only mods were exhaust and turbo porting a fuel pump rewire and some software upgrades. I commuted 50 miles from Long Island to Manhattan for at least 2 years. I had alternator/electrical problems and replaced it as my commuter then eventually retired it due to rust... I would assume the same or better MPG with my Galant GSX build, as I have a more efficient turbo (small 16g), Cyclone Intake, higher compression and the same if not more software updates.

A few more mpg is definitely attainable just by keeping it in open loop higher in the rpm band at cruising airflow and throttle. Or the opposite run the stock ecu full time closed loop and tune extensively with a wide band.

Dave W. is a tuner out of California that has said 46mpg was his personal record, with a fwd eclipse with 550cc injectors a 16g turbo and a taller awd 5th gear in his gst tranny.

 

[GSX_TC]

I'll be counting my MPG's again this year on the way to the shootout, my tuner asked me what speed do I usually cruise at then gave me a nice little cruise tune to go along with my entire tune so I'm curious to see what it'll get now.

 

[IncorpoRatedX]

My car is all stock except a k&n filter, highway I cruise at 70-75

My average MPG is 25-30mpg, I log my blended mpg every time I fill up.

I just recently replaced my o2 sensor because it threw a code once (which immediately went away seconds after the light came on)

With the old sensor I was getting 15-20mpg

Make sure your o2 sensors are good y'all /ubbthreads/images/graemlins/smile.gif

 

[BpuVR4]

Quoting GSX_TC:
I'll be counting my MPG's again this year on the way to the shootout, my tuner asked me what speed do I usually cruise at then gave me a nice little cruise tune to go along with my entire tune so I'm curious to see what it'll get now.



damn, the beauty of technology.

everyone else's responses are just as intriguing.

 

[belize1334]

I was getting ~22mpg before I rebuilt my head, which was burning oil through the valve-stem seals. When i got it apart there was a ton of carbon deposited on the valve faces as well as the pistons, all of which I cleaned up. My first road trip since the rebuild will be next weekend so I'll update after that - I'm hoping for ~28mpg. That's with stock turbo, cyclone manifold, 3G MAF, FIC 650s, Keydiver Chip, EvoIII 5th gear, 235/40/R17 tires, cruising about 80mph.

 

[Turbo99]

I'll measure it on my way to the shootout, but with mixed driving that's probably 75% highway my galant gets ridiculous gas mileage. It has to be right about or just north of 30 and I cruise at 70-75 mph.

Td06 20g, 720's, stock cams, stock longblock, evo 3 manifold, 2.5" exhaust, dsmlink etc.

 

[BpuVR4]

^ one of the biggest reason I would want to go to a bigger turbo ironically is so that i assume it's easier to stay OUT of boost. my evo 3 16g is fun, and maybe too easy to dip into boost. have never driven a 20g turbo'd car so can't speak from experience, but it's making it more tempting.

 

[coyotes]

it is hard to stay out of boost with a 16g. You have to cruise at 60 and hope there's no hills

 

[4Grim]

When mine was a daily...I would cruise at around 60mph for 20 mile one way trip to work and averaged 25mpg.

At that time car was on a completely stock longblock with a Evo 3 B16g and full 3" exhaust with boost set at 20psi.

 

[cheekychimp]

I'm not sure how accurate this is because I'm going off how many litres it takes to fill my tank each time I refuel and converting kilometres to miles since I get around 400 kilometres out of a tank if I'm not being stupid. If I do the math I get about 19-20 mpg which is actually pretty good I think since I can't really cruise for more than 20 minutes without hitting traffic over here.

I think if I drove this car in the States on your highways I could get closer to 24-25 mpg ... maybe more. Speed limits over here on our highways vary between 45 and 70 mph and I typically drive about 10% over like everyone else.

 

[mitsuturbo]

^^ Good to know that roughly 10% over is the acceptable limit in other parts of the world as well. /ubbthreads/images/graemlins/grin.gif

 

[gtluke]

generally I'm at about 4k rpm's, in the boost on a 14b, and getting about 17mpg. The evo/rs trans/rear rule!
If I was looking to save money while driving I wouldn't be driving a 25 year old modified japanese dodge.

 

[coyotes]

My gas mileage has gone downhill since I got the car back together. Been driving it same as before, but I swapped in a different used o2 sensor than the one in my car originally. Gonna put the other one back in or just get a new one.

 

[thecman02]

At 70mph on E85 tuned open loop at around 15.5AF I usually get mid 20's (23-27). With roof rack and accessories/bikes I'm on the lower side.

I have never gotten over 20 with city driving though. I just love accelerating hard.

 

[prove_it]

Really? I lean burn the crap out of my E85 and get about 14-16mpg.... at 85mph.

Otherwise, I average about 12-22 mixed pending on how heavy my foot is. At WOT it drops to around 1-2.....(just guessing)