Biogas A4 hits 227mph

[Fledermaus]

The silvery saloon is powered by Audi's twin-turbo 3.0-litre V6, modified to run on compressed biogas and putting out a frankly loony 700bhp.

That's thanks in part to sheer amount of bang in biogas, which has an octane rating of as much as 140, er, octanes. Hohenester says that, running on biogas, the engine is capable of developing over 800bhp, but his team had to turn down the wick a few notches to stop the Audi's gearbox from going ‘pop' in quite a spectacular way.

http://www.topgear.com/uk/car-news/biogas-2009-05-29

[NYC_SKP]

1. Good story, but LOL "Octanes"!

Octane is but one of many hydrocarbon molecules, including methane, heptane, et al.

From wikipedia:

"The octane rating is a measure of the resistance of gasoline and other fuels to detonation (engine knocking) in spark-ignition internal combustion engines. High-performance engines typically have higher compression ratios and are therefore more prone to detonation, so they require higher octane fuel. A lower-performance engine will not generally perform better with high-octane fuel, since the compression ratio is fixed by the engine design.

The octane number of a fuel is measured in a test engine, and is defined by comparison with the mixture of iso-octane and normal heptane which would have the same anti-knocking capacity as the fuel under test: the percentage, by volume, of iso-octane in that mixture is the octane number of the fuel. For example, gasoline with the same knocking characteristics as a mixture of 90% iso-octane and 10% heptane would have an octane rating of 90. <1> Because some fuels are more knock-resistant than iso-octane, the definition has been extended to allow for octane numbers higher than 100."

http://en.wikipedia.org/wiki/Octane_rating

[imdjh]

2. When they accidentally put regular in the Super tank

... they send a guy out who first tests the contents of the tank, which is now about 90% super and 10% regular. He then takes big jugs of stuff, and adds some of this and some of that, and the regular is now magically super.

[Fledermaus]

3. There is no octane in biogas, the octane rating compares any type of fuel ot octane.

Generally, what they add to regular is ethanol. Blenders can add up to 10% ethanol without having to label premium as gasahol.

[dipsydoodle]

4. The reference to "octanes"

is just a cynical remark typical of the guys on that program.

When you've got the time watch their antics here in their unsuccessful attempts to destroy a Toyota Hilux. Yu'll freak when you see part 3......lol.

part 1 : http://www.youtube.com/watch?v=Lrk6vsb77xk&feature=SeriesPlayList&p=793CABDF042A9514

part 2 : http://www.youtube.com/watch?v=0Uc4Ksz3nHM

part 3 : http://www.youtube.com/watch?v=Lrk6vsb77xk&feature=SeriesPlayList&p=793CABDF042A9514