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My 0-80MPH Air Speed Indicator showed up yesterday. It consists of a gauge, clear tubing and a hollow alimunim rod the size of a pencil. The hose connects to one end of the rod and the other end of the rod is to be mounted on the car with the opening facing forward. The other end of the tube connects to the gauge. When you blow into the end of the rod, voila, the gauge moves. Evidently I am quite a blow hard because it can easily peg it at 80 MPH.

The gauge came with a calibration test report. it was tested in 10 MPH increments from 20 - 80 MPH. The calibration is within +/- 1 MPH at all speeds.

So I did the install this morning. The tube is on the drivers side just under the air dam extending 3" in fromt of the bumper. There was already a hole in the bottom of the air dam and something to lever the rod against to hold it in place.

The gauge mounting was too easy. I have circular vents in the dash near each front window. I popped out the vent on the drivers side and popped in the gauge. It's a good press fit so no fastening required.

So I went for a test drive and it works great! The readings are about what I had expected, jumpy but still useful. I headed out for a test drive starting against the wind. At 55, the gauge showed 62. In the other direction at 55, the gauge read 50. So there was a 5-7 MPH wind.

The readings are fairly smooth except during wind gusts or when cars go by. As expected, cars passing in the opposite direction cause a spike in airspeed, 5-10 MPH. But what is surprising is that the increase lasts long after the car passes. When cars pass in the same direction you get a nice drop, again 5-10 MPH. It was fun drafting a tractor trailer. At 45 MPH, the air speed dropped to zero. Since the gauge does not register below 20 Im not sure what the actual number was. At 65, following at one car length, the gauge bounced between 20-30MPH. At a safer distance, maybe 4 car lengths, the gauge bounced between 35-45. Even at 10-15 car lengths there was still some benefit, about 55.

So this gauge will be fun to have and I will be recording relative wind speeds with my daily commute data. It should help to quantify the effect of wind speed on my FE.

Here are some pictures:
http://img223.imageshack.us/img223/4733/dcp59983tw.jpg (http://imageshack.us)
Front view above: Yes, it does need a wash.

http://img223.imageshack.us/img223/8730/dcp59999wz.jpg (http://imageshack.us)
Tube mounting. Prius in the background.
http://img223.imageshack.us/img223/2310/dcp60014ue.jpg (http://imageshack.us)

Gauge Mounting. It is starting to look like a cockpit in there.

so just what IS the airspeed velocity of an unladen swallow?

Europian or african?

BTW, the data gathered will be great. It will be good to quantify the various drafting technique gains.

Hi Dan:

___That is one great idea for automobile use! I have seen pitot tubes on planes for air speed measurement my entire life but never on a car …

___Good Luck

___Wayne

Europian or african?

What? I... I don't know. AAAIIIIEEE!!!

:D

I see the prius peeking under there!!

I was about to get these myself until Dan told me how much it was haha. I think i'll stick with a mini Canadian flag in the front ;)

That is a GREAT tool for long-distance drafting as I like to call it. I know on my Civic I had always noticed that I'd only be able to achieve about 37mpg on my ScanGauge at 75mph, but with even something as small as a pickup truck a good 8-10 carlenghts ahead I'd see it bump to 39-40mpg. With Semi's, I could leave a very healthy 150 feet or so which is almost a second and a half of following distance and still hold around 41mpg. That kind of made me a believer in trying to draft from a healthy and safe distance. I could still preserve a very good margin of safety and gain 5-10% FE effortlessly compared to no following.

Yes, even while not trying to draft there is a benefit when you are in traffic when everyone is travleing at highway speeds. The traffic acts to move a column of air along with it. I just sit in the right lane at 55 while the traffic passes on the left. The air speed indicator usually shows 35-40 MPH. So I am getting the benefit from others as they speed by.

I'll second the "good idea", and ask for a link / info on where to get one.

But the real reason I'm posting here is that I thought I spotted an inclinometer in the dash - if so, can you please post info on where you got that ? I've googled / e-bayed to no avail for one - best I could do was to find links to a OEM Range Rover inclin. that would take up half my dash (ok, 1/3 of the Civic's...lol), or precision equipment costing 1000's of $ (and not really intended for automobiles).

Appreciate any info on either or both :)

Here are two different types of ASI's. One Cheap and one expensive. I got the expensive one.:(

http://mikes.automated-shops.com/cgi-bin/webc.cgi/st_main.html?p_catid=37

http://mikes.automated-shops.com/cgi-bin/webc.cgi/st_prod.html?p_prodid=349&p_catid=37


I think what you saw was my vacuum gauge, not an inclinometer. I do have a combination compass, outside temp monitor, elevation display called a Wayfinder. I find it very helpful.

You know what else I realized when I was thinking about it this morning? Any time you head up in to higher elevations, it will under report too. It was likely calibrated for near sea level, and a quick yahoo check shows Pittsburgh airport at 1204 feet ASL. That's still pretty handy though, much the way it's intended purpose of measuring wind / drafts is handy to know.