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Hey folks!

Well my first attempt at hypermiling paid off pretty well. My last tank I got 36.6 Mpg, which is just barely below the EPA highway estimate. So, I didn't do great, but a lot better than I had been getting before.

I'm trying to improve my numbers, and have a few questions in that direction. My tires were at 27 psi, the recommended is 29 psi. I set them to 34 psi. I would assume that 5 pounds over is safe, is it safer/better to go any higher than that?

Are there any good articles for pulling a pulse and glide in a non-hybrid vehicle?

My odometer is digital. It takes about three seconds from me turning the engine off for it to calm down enough that it won't fire right back up when I turn the key back to "on". I haven't been able to see that it's tracking mileage when the car is off. Does anyone know if it will indeed continue to track my mileage, or am I getting "free" miles on the car that don't figure into my overall FE?

Thanks in advance!

Welcome to CleanMPG!

About your odometer: I believe it's not counting during the time the key is off. That's the way my 10-year-old Honda is, so take that for what it's worth.

About the tires: There is a small bit of print on the sidewall of the tire itself that says "max pressure 44 psi" or something like that. Most are 44. Anything up to that is perfectly safe. Many here go much higher than that, even. Read this thread: http://www.cleanmpg.com/forums/showthread.php?t=1881&page=2

Welcome to cleanmpg!

Good work - you got an increase of 13% - and you've just gotten started.

The advice I've seen is to set tires at "max sidewall". "Max sidewall" being the pressure limit embossed on the tire sidewall. Some folks like to go higher than that but I'd want to know more than I do now before exceeding the tire's rated pressure.

See this post
http://www.cleanmpg.com/forums/showthread.php?t=3332

Be sure to check pressure when tire is cold, after sitting idle for several hours or in the morning before leaving for work. The tire's rated spec is for a cold tire, and takes into consideration that pressure will go up approx 4 psi higher than spec during use.

Since I always have to drive at least a mile or two to get to an air pump I can never pump up a cold tire. So when inflating I estimate the increased pressure appropriate for the fact that the tire is warmed up and inflate to max sidewall plus 1 - 4 lbs. Then I check the tire next morning when it's truly cold and let out a bit of pressure if needed.

Re. the odometer, I had the same question and answered it for my car ('89 Volvo) on a long downhill glide. The trip odometer reads in .1 mi. increments; the glide was more than that and when I restarted it there was no evidence of the added mileage on the odometer. But your newer car may track that mileage correctly; you'll have to test it yourself - safely of course.

I will certainly go and find the max sidewall number and pump it up to that. I have the advantage of having a gas station with an air pump about 3 blocks from my house, which helps out with not having to compensate for a warm tire and such.

Thanks for the links, I certainly do try and search and such, there is just such a large pile of information here that it is tough to discern what is helpful from what isn't.

Thanks again. :woot:

About your odometer: I believe it's not counting during the time the key is off. That's the way my 10-year-old Honda is, so take that for what it's worth.

Tried this last night for a definitive answer, and it turns out that my odometer definitely does not tick off mileage while the key is off. This could be good for my resale value if I did it often enough, but it would make calculating my MPG a little more difficult than I like. Maybe I should look into a kill switch or something like that.

This tank is going really well. I don't have a scangauge to tell me exactly how well I'm doing, but the needle is sitting just below the half tick, and I've got 224 miles on the tank. Usually at this point on the meter I'm at around 180-190 miles.

I've also discovered that this car clutch starts incredibly smoothly. At ~15 MPH in 5th gear it starts without any odd noises, and completely lurch free. So I have a few more spots in my commute where I can safely coast without the engine on, since I don't have to lose my brake lights or signals for a second while I turn the key.

What you could do is just drive the trip to get actual mileage and use that.

What I do since My driving gets me about 1/2 mile less than actual is that I just go with what the car reports as miles driven and use that. Sure it is an underestimate of my actual mileage, but I'm not in a contest with anyone but myself so I can deal with it.

What it does do is to give you the actual mileage of when the car is on so you can work more on driving technique.

Ultimately I wouldn't worry too much about it and just use the cars odometer too keep things simple.

Just found this site when I googled gas efficient mods for an XA. I've been hypermiling for about a year. I coast with the engine shut off quite a bit. My question:

Is it bad for the starter to keep shutting and starting the engine? If I see I can coast or I know a light coming up where the engine can be off for more than a minute, I'll turn the key off.

If you use the starter to restart your car then it will cause more wear. However, thats usually not a concern as we prefer to bump start (use the clutch) our cars. It uses less gas and the clutch wear is minimal.