I get about 15.7 mpg with a combination of city/highway driving. Granted I have PPE headers, deleted resonators, and universal borla mufflers.

 

...I'm doing an update to this older posting of mine, as of today, my computer readout is @ 21.7 combined

 

Haven't looked at my trip computer but I've been getting over 350 miles on each tank for the past couple of weeks, ever since the weather is starting to get a little warmer. Driving is 60% highway 40% city.

 

My actual calculated MPG is in my signature below.

For my SC430;

Best tank 23.7
Worst tank 18.3
Average over 1,400 miles is 20.2

 

I had her up to 120mph on the I-95 yesterday and had good MPG. That water injection sure is working great!

 

Hey bgw, that's sweet! I may be dense but what do you mean by water injection? Are you running an intercooler?

 

I was playing around!. I figured some of these older guys would be all over the water injection! Here are a couple of lines from wiki about water injection.

It was used historically to increase the power output of military aviation engines for short durations such as dogfights or takeoff, however it has also been used in motor sport and notably in drag racing.

The only thing real about my post was the run up to 120 on the interstate, man these cars are smooth!

To get my car to show 39mph was easy...just hit reset and decelerate. ;-)

 

I was going to ask if that 39 mpg was downhill with a tailwind, in neutral...


Yeah, most of those "water injection systems" are a hoax anyway.

 

I thought about doing this as well. Looks cool but I don't need more problems in case something goes wrong :-)

 

You are a wise man!

 

Here are my real world numbers : 20.10 MPG for the last 15,250 miles over 3 years using 93 octane gas. The number is from actual mile and fill-up gallon calculations with spreadsheet.

This is a 2004 with the 5 speed auto trans. Currently at 110,800 miles. Engine and exhaust are stock. Car is not driven much during the winter ( never is snow or on wet / salty roads ). Hilly terrain just north of NYC, mostly back roads with >40 MPH speed limits. Pure highway at 65 gets 26 MPG.

I call it the economy car. The Sienna w/AWD only gets 17 MPG average and never more than 22 with pure highway.

 

I was getting about 24 mpg on the highway this weekend, so that seems about normal for our cars?

 

I just did a trip of just over 2,000 miles, almost all of which was highway driving, and my average was just under 25 mpg. I kept real data for that computation, but the computer in the car gave me almost exactly the same number, so that seems to be well calibrated.

 

I just did an 800 mile trip from Shreveport, Louisiana to Chicago, Illinois. It took me about 11 hours. Mostly highway. Doing about 75 average mph. Unfortunately I did get a ticket for $120 an hour outside of Chicago for 86 in a 70, or so the jerk of a police officer says. I had my cruise set for 75mph. Overall my gas mileage was about 22.9 mpg. Pretty upset about my ticket, but I guess that's on me. He was hidden, lights off. Radar detector caught him at the last moment. Not happy at all.

 

Sorry to hear about the ticket...

It might be worth testing out the Waze app, police are marked by other people and when you are on a busy road, it works very well.