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I'm going to be taking a relatively short (~100mi each way) highway trip this weekend. I know that the highway is not the optimal environment for FE due to the high speeds but I would like to do the best I can. I have already taken the first step on a few shorter stretches, which is to drive below the limit rather than above it. (I had been a 72-75mph driver and now I'm shooting for whatever the right lane is doing, preferably 60.) I know about the multiple variations on drafting, some of which will be more useful than others. Then there is DWL if I can keep from losing too much speed and there might even be an opportunity for coasting into zones where I can get away with lower speeds. The roads are mainly four lane (two each way) interstate with 65mph PSL, with some short streches at 50-55mph. It's a familiar route which will make it easier to anticipate changes in terrain and traffic control. Is there anything big that I am missing that would help in highway driving?

I just thought of a more specific question that has to do with DWL. I am generally hesitant to let the car pick up too much speed as I descend a hill. I won't resist gravity but I won't give it too much help, either. I'm concerned that this is hurting my overall FE when I start to go uphill again because I'm not carrying as much KE to help the engine push me over. This results in a need to get deeper into the throttle.

So here's the quandary: When descending toward another climb I can't decide if it is better to coast down (either FAS or NICE-on) and enjoy the 100-150mpg ride until I get to the bottom, or to keep a light touch on the throttle, decreasing my instantaneous FE (could still be in the 60s or 70s) but keeping more momentum for the next hill. I think that getting better with this optimization will really help me out, especially on these hilly New England highways. Can you guys share experience in finding the balance?

Hi Brick:

___Because traffic is very rarely if ever bumper to bumper out on the highway, try and crest at a below the speed limit speed and FAS to a higher then speed limit speed by the time you hit the next trough. This is a problem with long highway drives in that you are usually in unfamiliar territory and have no idea as to how fast to hit a trough or crest for maximum FE advantage through the next peak or trough. Moving slower is never a problem as long as traffic is light to the rear and it will be clear far more then you have ever thought possible once you start to pay attention to what is going on back there. Ridge Ride when slowing on the ascent, gliding over the crest, and keep it up until you again hit the limits on the descent. A FAS is by far your best bet as long as you can maintain a max of maybe 10 - 12 over on the descents.

___If you need any other assistance before you leave, just ask as I will be on again/off again throughout the day and evening.

___Good Luck

___Wayne

I fas alot. I fear no fas. ( sorry :) )

I load drive up hills as best as I can. If I know I have a killer good fas on the other side. Just as I crest the hill I bring the speed up all I can. Then throw it in netral and turn the engine off. There are a couple of areas where If I have enough speed toping a crest I can fas down the other side,, then up the next hill and then drop into a lower speed limit area and get a 2 mile fas!!!

Ive used google earth alot to refresh myself with roads and elevation changes. I will be launching into a study of interstate 40 this weekend and the hwy from Flagstaff to Pheonix.

If you want you can use my address, 821 s. okmulgee st. okmulgee, ok. 74447 to 5484 s. 103rd e. ave. tulsa, ok. 74146. On google earth and look over my daily drive. It will show elevations and other features. There minor looking changes but can result in some awsome fas action. I think my white ranger is in the parking lot here at the office.

Thanks for the advice, guys. I am intentionally waiting until after the Friday rush to hit the road so that I can deal with as little traffic as possible. FAS is a definite possibility since many of the hills on this drive are pretty steep. I probably should check out the route on Google Earth to refresh my memory.

Oh, an a totally unrelated note, P&G in town is my new god. I just did a ~3mile segment of light-to-light, 30-35mph driving around town after work. I usually get crappy mileage just because of the lights and turns but somehow pulled off >35mpg, which combined with the longer >37mpg drive home from work pulled today's average out of the gutter. Pulse in 5th through the trough, load drive up the small hill, neutral down the back side, get back in 5th for a little speed, coast...lots of fun :) That's easily 10mpg better than if I just keep a constant speed. I think I'm starting to get the idea now. I'm starting to realize that this is at least as much about art as science.

Hi Brick:

___A 10 - 15 mpg improvement in just 3 weeks of discussion! Another week or two and 40 + around town will be your new minimums! Just wait until you see your first 50 mpg segment :o

___I knew you had it in you and keep up the great work ;)

___Good Luck with the trip.

___Wayne

Hi Psy; I am quite familiar with I-17 from Flagstaff to Phoenix. It it a SUPER chance to FAS. You travel from 7112 feet of elevation, to 1020 feet in Phx. It is 132 miles. There are LOTS of long downhill sections, then flat and even a couple of short up-hills. The freeway is pretty wide, with not too much traffic between milepost 330 and 240.

I just hope you don't have to ever go BACK uphill to Flagstaff???

at least this proves my point, "you don't have to do things slower, just differently". became your time to destination will almost be the same with the exception that you spent less energy overall to get there.

People just need to sit down and think for just a minute about their driving habits...

Finally got some time on the highway. My first observation is that hypermiling on the interstate with relatively light traffic isn't nearly as difficult as I would have expected. I've been keeping my speed in the 58-65mph range (sometimes touching 70 on a downhill coast) and I can still maintain really high instantaneous FE on level pavement. Second, I'm impressed with how high I can keep FE while climbing if I'm really careful about keeping a light touch on the throttle. I was able to maintain 26-28mpg up most hills at ~60mph, and load driving really helped to reduce the duration at steady speed. Finally, coasting down the hills does huge things to FE! I didn't even FAS (I wanted to see what kind of numbers I could get without it) and NICE-on coasting let me sit at 200+mpg instantaneous for fairly lengthy stretches. Hills that weren't quite steep enough for me to maintain speed still allowed me to P&G nicely between 58-65mph. That resulted in a 43mpg segment according to the scangauge between western MA and Albany, NY.

The really cool part is what I did in my girlfriend's Volvo XC70 today. She drove one 70mi segment and got her usual average of 23 or 24mpg. I drove the the return trip and applied nothing more than load driving, bringing the trip average up to 29.4mpg :D . That beast can really hypermile! That means that I was probably in the low 30s for my segment. She kept yelling "How are you doing that?!?" as the trip computer's average kept going up. EPA is 19 city 24 highway for that car.

Incidentally, my last tank in the Accord came out to a hair over 36mpg at the pump in mostly short-segment driving. My revised goal is to be hitting consecutive 40+mpg tanks by mid summer.

Hi Brick:

___You are really starting to perform and I for one am very glad to see you doing it. Not let’s get some pics of that XC70’s FCD and your Accord via the SG up in the non-hybrid screenshot area for others to follow your lead :D

___Good Luck

___Wayne

Will do! I'll have to make it a point to put my cheap digital camera in the car before the weekend. I don't want to make any rash predictions but I think I feel a record tank coming on. (**Knocks on skull in lieu of wood**) The Scangauge is sitting at 39.2mpg @ 230mi and I'm motivated to practice FASing so that I don't ruin it too much during the weekly grind.

This is way too addicting. :D

Hi Brick:

___You are starting to bump up towards maybe 80 - 85% of your capabilities now imho. Just a few more weeks ,,,

___How did your tank finish up anyway?

___Good Luck

___Wayne

I just tanked up today with a new personal best: 38.25mpg over 471.6mi, ~350mi of which were on a very hilly highway. The route I had to take climbs from 150ft elevation to 1500ft and back, making for some frustrating ascents followed by some excellent FAS runs. I'm extremely pleased with this result, especially considering the hills, the chilly mornings, the rain on Friday, and the MTBE sticker on the gas pump last time I filled. (OK, done making excuses ;) ) No doubt there's still plenty of potential left to work with here.

And another personal best, 80% highway mileage: 481.9mi and 12.261gal =39.3mpg

Still making the slow climb to 40mpg!

Hi Brick:

___You are so darn close that I bet you can smell your first 40 mpg tank!

___May the wind be at your back and the hypermiling gods be clearing you a path … And don’t forget to keep that accelerator pedal under control ;)

___Good Luck

___Wayne

**** even an accord beat me ;(