The official EP3 hypermiling club

[Deadphishy]

I sometimes hypermill the focus. And I did have my EP tuned really lean 15-16:1 afr for awhile. I was getting high 20's in the city and 36 on the freeway. with a 240+ whp k24. Ceramic coated forged pistons ftw.

[gribly]

Don't shift into neutral and coast, it uses more fuel. According to the OBD link wifi thingy a friend of mine has, my EP (stock) won't use fuel when coasting until it hits idle speed it seems.

[newep]

I tried a bit of hyper milling mods last winter and noticed a slight increase in MPG (about 30-40kms better per tank on the hwy).

I switched to the lighter rsx rims.

Made 2 underbody trays out of 1/8inch mold-able plastic sheeting. One to cover the engine bay attaching to my D3xx brace, I really made it cause i needed something to stop snow and shit from getting caught. This also quieted down some road noise. and since i was already making a tray. I made one that covered from the gas tank to the rear bumper up into the passenger wheel well. and no theres no diffuser:(

I also installed Aspec struts and new bushings,( slightly lower rider height might have helped??) 3 inch CAI, I have a RBB manifold so i needed a better intake.
I had already switched to a 6sp lsd tranny the year before.

So I'm guessing the lower rpms and less wind resistance made the biggest differences.

[azsi]

I have a stock ep and when I use 91 octane gas I get better mpg but I hear it burns hotter and hurts the engine in the long run..so I may go to 89 octane ..I was told to go with what the manual says and also stick with the oem spark plugs as well.

[poeticfinesse21]

I used a mix of 89, 91 and 93 octane gas over the period of a few months to see if I would gain MPG's and I didn't, so I switched back to 87

[ryboto]

My k24 tune set the cruising afr to 14.7... any danger setting it higher? Figured the tuner would try that if it was safe, since I did tell him I commute...

[04JRSCEP3]

I've had my 04 for almost a year now. Bought it with 119,000 performed the standard maintenance (oil change, transmission fluid). I am running a supercharger street kit. I always use 91 octane fuel (usually from chevron.) On a few of my recent tanks I have tried a couple of the hyper-milling techniques, I just don't have the patience to "hyper-mile" on a regular basis I HAVE TO PLAY. I have noticed that anytime I drive under 65 my fuel consumption drops drastically. My last tank was my best I filled up right at the 1/2 mark and managed to squeeze out 34.9 MPG driving between 64 and 55 miles per hour and neutral casting down hills. Eventually my goal will be to get the 6th speed from the tsx / 06 si "just to pick up the pace a bit" with lower rpms at a higher speed.
http://www.fuelly.com/driver/jrsc04/civic-si

[04JRSCEP3]

I have a 2004 EP3 with 132,000 miles, 17' HFP rims 215-45-17. Unfortunately I don't have the patience to maintain "good driving habits". On a few occaisons I have tried cruising at 60-65 and coasting on hills (60 mile commute round trip to work everyday with a lot of hills.) My best tank so far was 34.9 mpg over the course of 1/2 a tank. 208.7 miles 5.99 gallons of 91 Chevron. My average is only 26.6 usually spirited driving and 80 on the highway.