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Last weekend I drove with my wife from El Paso, TX to Phoenix, AZ (~415miles). Before my hypermiling days this trip could not be made on one tank of gas. I would have done it at 80-85pmh with cruise control being the only fuel saving technique. I decided to apply what I have learned in the last few months and made it my goal to make it to Phoenix in well under 1 tank. The highest pressure I had used in my tires was 46psi; I increased it to 49psi for the trip. I planned to add wheel covers to all four wheels but only had time to do the two rear wheels. I'll post pictures of the covers later. I also covered two small sections of the front grill. My strategy was to distant draft RVs and Semi-trucks that were traveling at 90% speed limit and appeared to be using cruise control. The speed limit is 75mph most of the way to Phoenix on I-10. I managed to find vehicles traveling 65mph most of the time but did draft behind some vehicles going 70-75mph after my slower draftees exited. I ended up averaging 36.7mpg on my vehicle rated 20/26 by the EPA. At this mileage I had 30% of the tank left. This is my best tank so far:Banane04: . I suspect drafting had the largest effect. At 49psi my vehicle is alot louder and stiffer than stock. It was a bit wearing at times on bad roads but well worth it. It is not so much of an issue during shorter in town commutes. Running 49psi obviously reduces rolling resistance. My garage at home is flat and then the driveway has a gentle slope. In the mornings, I stick my leg out of the driver's side and push my car backwards until the rear tires are on the driveway. I then close the door and coast backwards into the street with the engine off before starting the car and moving forwards. At 40psi I required several hard pushes with my foot before the rear tires were on the driveway. At 49psi all I need is a gentle nudge. The first time I pushed off at 49psi I had to apply the brake because the car quickly moved backwards and I almost didn't have time to close the driver's door before it hit the garage door frame. The steering is also much more direct in a positive way and provides better feedback at 49psi. I hope the increased tire pressure and rear wheel covers will help make up for the colder temps that had dropped my fuel economy by about 2mpg during in town (75%highway) driving.

Hi Antrey:

___Thank you for that story! I wish there were a lot more in the world like you in this day and age … I cannot do much more then state the above other then to personally congratulate you for your efforts. Thank your wife for all of us here as well since she was probably a bit perturbed at first until she realized the results upon your arrival in Phoenix. From the results, you not only smashed the EPA but proved to all that taking it a little easy on the pedal and setting up your vehicle for travel can do wonders for us all.

___Good Luck and thanks again.

___Wayne

Hi Antrey:

___Thank you for that story! I wish there were a lot more in the world like you in this day and age … I cannot do much more then state the above other then to personally congratulate you for your efforts. Thank your wife for all of us here as well since she was probably a bit perturbed at first until she realized the results upon your arrival in Phoenix. From the results, you not only smashed the EPA but proved to all that taking it a little easy on the pedal and setting up your vehicle for travel can do wonders for us all.

___Good Luck and thanks again.

___Wayne

Thanks for your positive reinforcement, Wayne! Yeah, my wife was a bit perturbed from traveling at, "RV speed" and delaying our arrival by about 1hr. She was pleased by the result, though, and congratulated me for the effort. The fuel savings payed for some of the furniture we bought at IKEA on the way back.

Attached are pictures of the wheel covered, the minimal grill block done so far, and a picture of the beautiful wheel before being covered:( . The grill block picture just shows the left side (driver's point of view) of the grill being blocked but there is a symmetrical section on the right side that is also covered. I'm planning on using a black center cap instead of the mylar tape on the wheel covers eventually and also to remove the mylar tape from the front grill block that was used to hold the coroplast in place as the silicone dried.

http://9-2x.dynamic-dyno.com/images/Aero_wheel_covered.JPG

http://9-2x.dynamic-dyno.com/images/Aero_grill_block_step1.JPG

http://9-2x.dynamic-dyno.com/images/Aero_wheel_uncovered.JPG

The rear wheel covers, partial grill block and 49psi pressure definitely seemed to help this last tank. My mileage had dropped to ~30mpg in mid Fall but with these simple mods I obtained my best in city tank ever, ~32.5mpg, slightly besting my highest Summer tank.:woot: Front wheel covers will be installed today along with some additional grill block.

Hi Antrey:

___I see your Saab 9-2X is equipped with some Bridgestone RE92A’s. That alone is a great start to higher FE ;)

___Good Luck

___Wayne

Well, I was dreading my day trip into the mountains of New Mexico to take the kids sledding in the snow. It was a 310.7 mile round trip going from 3750 feet up to 9350 feet and back down. I was sure this tank would bring my average down. I added front wheel covers of identical construction to the rears and increased pressure up to 50psi from 49psi. The steepest climbs were done at 10mph below the speed limit and I took advantage of all steep down hills for engine off coasting and slight down hills for pulse and glides (which I had never really performed before.) On the way back I was able to coast engine off for over 20 continuous minutes on one occasion! (~15miles) and about 15 minutes on another (~10miles). I got into town, filled up at the same pump, and was pleasingly surprised to find my best FE average ever, 37.64mpg!:Banane49:

Hi Antrey:

___Way to kick some FE @$$! A personal best in mid winter with a mountain in your way has got to be the best way to punch the EPA right between the eyes!

___We have a lot of great hypermilers here at CleanMPG who really make me proud and I want to pass on a well deserved kudo and welcome you to that same list given your efforts today :D

___Good Luck and congrats.

___Wayne

I managed to set a new personal best, in city tank this week. Most of the tank was driving with an extra 250lbs in the vehicle from carpooling with my wife and two kids but it was the first in city tank with front wheel covers and hood scoop covers. The improved aerodynamics and faster warm up seemed to more than compensate for the added weight. My previous in city best was 33.1mpg with only the rear wheel covers installed. This week's tank netted 33.6mpg with four wheel covers and hood scoop cover installed. It would be nice to get into elite range, 34.5mpg in my case, but without a full belly pan more extensive grill block and rear wheel well covers, I don't think I can consistently maintain that level.

If anyone is wondering/raising an eyebrow at my lack of updates for the 9-2x, let me explain. I've been trying to sell my 9-2x since January and have returned all FE mods pretty much back to stock. Few potential buyers of a performance vehicle are going to appreciate coroplast siliconed to the exterior and rock hard 51psi in the tires. Additionaly I've been trying to drive it as little as possible to keep the mileage down and reduce the risk of getting into an accident before selling it. I'll be looking for a mid 90's Civic HX or VX to replace it.

antrey,

We look forward to hearing about your next vehicle!