Mileage Marathons

Guys,

I have heard about these Mileage Marathons where the mileage returned for any vehicle used to about twice or thrice the mileage in normal driving conditions.

What do they do to get that mileage in the race? Do they modify their cars?

How is this mileage achevied?

Can someone throw light on this..

There are a number of techniques for getting extremely good mileage out of a car.  Many of them aren't safe because they involve driving very close to another vehicle or coasting with the engine off (so no power brakes/steering).

The most entertaining example I can think of is a contest Car & Driver magazine won in a rather sleazy way.  They got a Hybrid car over 100 miles/gallon (more than 42 kmpl) at highway speeds.  I think it was a Honda Insight.  They used a combination of racing tactics and one of the biggest gas guzzlers ever.  They built a wooden frame and attached it to the back of a huge SUV.  I think it was a Ford Excursion.  The Excursion never sold well due to being too big (3+ tonnes!), too expensive, and ridiculously hungry for petrol.  I'm not sure it was ever intended to.  It made a really great draft mule for an FE contest though.  Now the racing part comes in.  If a car is following closely behind another vehicle, its engine doesn't have to work as hard because the vehicle in front does all the work of pushing the air out of the way.  The Car and Driver team drove the fuel efficient hybrid car just a few centimeters behind their gargantuan SUV fitted with a custom wooden frame designed to push even more air out of the way.  Arguably they cheated, but using a truck that gets maybe 4-5 kmpl on the highway as a draft mule wasn't against the rules of the particular contest.

Stupid race rules, if it was that way!! Any kindergarten kid in the field of hypermiling knows that drafting gets rid of aero drag, and hence eliminates about 80% of expenditure (figure is random, but the aero contribution is that huge) at highway speeds.

cleanmpg.com regularly conducts mileage marathons for it's members, where such crazies probably don't participate, and the figures they get are quite good. Generally they fill each vehicle from dry tank to a specific amount of fuel, and let them run dry while passing through real cities and highways. So the figures are authentic, and attributable only to driving skills and vehicle thirstiness in general.

I personally believe that tracking tank to tank fuel consumption gives a cleaner picture of hypermiling, and have seen reported a 1500 cc petrol vehicle get the owner ~30 kmpl (70 mpg) without any modifications at all. The person is PaleMelanesian (user ID) on ecomodder and cleanmpg. They have his fuel logs on both sites.

Thanks Mike & Krishna.

@Krishna - i also read some of your other topic on increasing mileage on HC. Have you managed anything yet to a substantail amount? i really lost track of that thread.