1998 Civix HX... I want 50mpg!!!
 

Getting ready to drive a 98 hx from LA to Kansas, I am willing to try some experimentation if anyone has any ideas. tried to pick a time when I could bag using a/c. Want to try and get upper 40's mpg, would appreciate any ideas over highly inflating tires and leaving windows up. Thanks, Frank

My wife has a '98 HX and regularly gets 46 - 49 mpg during the summer on mostly highway, 65-75 mph driving and a bit of stop and go rush hour traffic. The only things I've done are

1) overinflate 35 max psi tires to about 38 - 40 psi, and they weren't LRR tires anyway. I just bought 4 new Nokian i3 tires to replace them. Haven;t had a full tank yet to calcualte the MPG.
2) formed a small piece of coroplast behind the driver's rear tire and attached it to the underside to direct the air under the car out underneath the bumper rather than directly into the inside part of the bumper to prevent the parachute effect. the same could be done on the passenger side, but I haven't gotten around to it
3) lower grille block

From my highway driving experience with my VX civic, I've found that if I can avoid going too much over the speed limit my MPG will go up dramatically.

Most used cars I've bought have always needed a tune-up, so I wouldn't get too disappointed if you don't reach your 50 MPG goal quite yet. I'm sure it'll be possible in the future once you get used to driving the car more.

thanks for your help, I am going to try the under car trick, thanks

I get 50mpg at like ~60mph and i have a dx...just slow down or drive after trucks...even 3-4 cars distance from the trucks they absorb most of the wind..

Compaq, your gaslog only shows 44 mpg for your best tankful, nothing close to 50 mpg. Or were you referring to the instant readout on the Scangauge when driving 60 mph or behind trucks?

Do you have a good synthetic transmission fluid in the car?
Also rip out any extra weight you may be hauling around with you.
Make sure you have a new air filter in the car when you leave on your trip.
Also run a good fuel system cleaner through the fuel system. Redline S1 and Techron are two very good over the counter products.

Also if your capable of doing it leave at 8 pm on your trip. That way you will not be driving in the hot sun. The first 10 hours would be under nightfall and cooler temperatures. There would be less need for the AC to running during the night hours.

I would caution you if your not a "night" person driving all night can be dangerous.

At least 3 to 4 mornings each week a trucker falls a sleep on the Pennsylvania Turnpike causing one side or the other to close for a few hours for clean up.

you can break 50 mpg easily. i averaged 45 mpg with a ex transmission when i did 70% highway and 30 city. now i do 100% city im getting 35


on a road trip, i averaged 46 mpg going 70 mph at 3000 rpm on my ex tranny, you should get at least 55mpg if driven slowly

I drive rarely on the freeway now...in fact the last 2 weeks I was only on the freeway for maybe 15-20 miles..

I was referring to the Scangauge 2 readout when I drive 60mph..it shows 50mpg or sometimes more. Driving behind trucks usually the readout dispalys from mid 50's to high 50's mpg...

I'll start driving mostly freeway at the end of May so the numbers should go up..

mpg
 

great info, thanks everybody!!!!!!!

I tried 2 weeks of hypermiling. Despite several 50+ mpg work drives, I only got 44.3 and 45 mpg on my 99 HX MT. I'd probably break a 50 mpg tank only on a long road trip!

Driving style will do it, for sure. My best in-town drive is 77mpg (scangauge), and my best highway is 75.2 over 150 miles. This is using all the tricks, including Pulse & Glide. Read the articles at CleanMPG for details. I'm not sure you'd want to go that all-out across the country, but at least keep your speed down.

Lower grill block is a good suggestion, to a point. On our cars, only the right-hand (passenger) 1/2 of the grill actually has engine radiator. You can block off the other side if you don't need the AC. With temperature monitoring (scangauge), you can block some of the right side. It'll help with aerodynamics. For a temporary block, you can use duct tape or clear packing tape. Also look at covering the upper grill. Not much airflow through it, but an aero disturbance still.

mileage
 

did the 1600 plus miles averaged 40-42 doing 75-80, I hated being in a hurry, but hurt my back and every extra minute was hell. Dropped to 65 and got 43+ but was hitting big time wind. I think if I did 60 I could have gotten 45mpg, tires at 35lbs, no wind, no a/c, nice trip, and sure beats filling up my Avalanche at 90 bucks a fill, it was nice to do 300 miles at 7 gallons of gas!!! Frank

My ScanGauge read 173mpg doing 60mph going downhill in neutral, does that count?

my scangauge reads 9999mpg doing 60mph downhill in neutral..

i turn off the engine going downhill because you're going the same speed and don't need to use your engine...

My best city is 54 mpg with FAS P & G. Won't FAS P & G on a hwy unless I'm the only one there. Then I'd do 75 to 50 FAS P & G.

Dude! You've got to slow down. I've done 45-60 highway P&G, and got, as I said above, 75 mpg. Your car could do even better than mine in the same situation.