Fuel Economy, Gas Mileage, HOW TO???

[showtime7]

So I'm taking a long trip from Western MN to Western MT and wondering how fast I should cruise to get optimum fuel economy? When I drive interstate at 75mph it sure does seem the engine is spinning to fast. When I drive 55 it seems to be lugging it too much. What is the best speed to drive? What RPM do you guys tend to shift at when driving in town. This motor makes so much more torque than what I'm used to driving, so I don't know how to drive it for best fuel economy. Please help!!!

[navylife59]

The lower RPM's (w/o chugging) you shift, the better the fuel economy. This maybe impractical due to traffic conditions.

80MPH your cutting about 3700RPM. Not good for gas mileage. 60MPH with cruise control on, windows up, and no A/C, no extra weight is the best it is going to get. Of course, downhill with a strong wind behind you would be even better Tires inflated between 32-35PSIG. Mileage tests are based off of 55MPH on test tracks in the best conditions.

Other tips would be put the transmission in neutral going down hills and steady downgrades to take advantage of gravity. With the transmission engaged (std/auto), it acts as an engine brake thus robbing you of free energy. This is not always practical. Before you make it to the bottom of the hill put back in gear and speed up (don't lay hard on the gas) a little going into the hill. Now, as gravity starts working against you, start easing off on the throttle. When you have it down, with most hills you will end up with nearly the same speed as you had before. If you slowed down some, that is OK. Just slowly speed back up to your original speed. Remeber, the name of the game is not speed but gas milage.

Note: Cruise control is opposite of this. It wants to maintain the exact speed that it is set for, even on long, steep hills. It will go WOT and waste alot of gas so turn it off in hilly areas.

[smaterblah]

Has anyone had any luck w/ K&N air filter increasing their gas mileage btw?

That is one of their claims, along w/ a small HP increase...

It's only $50 @ Pep Boys. might be worth it. anyone have any comments on it?

What did you end up for Mileage Showtime?

[showtime7]

Well, on the way out there I drove about 80 mph the whole way and got 26-27 mpg. On the way back about 65mph and coasted down hills. I even drafted a semi for about 10 miles. I got 33 mpg and think it could have been better if I wouldn't have raced an Accord. I have a K&N. I bought it with the car. Do you like washing filters? I don't.

[navylife59]

MPG is entirely subjective. Too many variables. I wish there positive cylinder displacement for highway cruise. 2 cyl burning gas is going to cut your cruise fuel burn about 40-45%.

[smaterblah]

You mean like a prius or something?

[navylife59]

Like some Chevy trucks. You don't need all cylinders banging away to maintain a moderate cruise on a level road, so Chevy cuts fuel to opposing cylinders symetrically. This is just like a P-3 Orion aircraft cutting the #3 engine to conserve fuel when loitering over a target area.