Yes it was common to run these wood 'digesters' on cars throughout Europe during WWII when petrol/gasolene was rationed and often hard to get.
As for steam cars, yes they can go fast - Jay Leno a couple of years ago was clocked over 75mph on a US freeway in a 1906 Stanley steamer running on kerosene. Some modern ones have been produced by individuals - but there were some experiments by the big manufacturers in the 1970s, including Saab and GM - neither put the car into production though - a great pity.
As for steam cars, yes they can go fast - Jay Leno a couple of years ago was clocked over 75mph on a US freeway in a 1906 Stanley steamer running on kerosene. Some modern ones have been produced by individuals - but there were some experiments by the big manufacturers in the 1970s, including Saab and GM - neither put the car into production though - a great pity.