Originally Posted by RickB
What does that mean?
Some reading of the literature on natural gas fueled engines might be in order.
Sir respectfully but what is a natural fueled engine? Is this opposed to an UN-natural fueled engine?
Lets just compare two types of engine for a min. lets take a diesel and a gas engine making...oh say 350 HP. Now go buy the latest and greatest you can that will fit in say a 40 foot boat in a twin configuration,nothing fancy just go to any boat show.
Ok cool... now look at what you have, of the two engines which has the most new technology in them. Which seems fairly unchanged over say the last 10-20 years? What engine is being refined seemingly every year to give greater power and better economy? What direction is Europe taking?
The gas engine is fine but due to the way it operates it is very limited in the way of further advancement (see stoichiometric mixture)
and unless greater advancements in ceramics progresses they are really at the lean ratio limit and the compression limit given today's fuels and reduction in anti-knock additives. We really are at the peak in spark ignition engines for ground transportation, heck that's ok we were there in aviation in the late 50's when all the HP that could be wrung out of an engine reliably (or not) was reached. Pratt & Whitney R-4360 Wasp Major
The point is simple, the money and research are going away from spark ignition and on to higher compression to use less refined fuel as well as Bio-fuel engines with better output and less emissions, these are the facts.
Diesel now outsells gas in EU and the trend is sharpley curving upward.
Vehicle Technologies Office: Fact #716: February 27, 2012 Diesels are more than Half of New Cars Sold in Western Europe
Just look at what the last 40 years has done for diesels as opposed to gas engines.
Since 2006, every car to win the famous endurance race — the Audi R10 TDI, Peugeot 908 HDi FAP, Audi R15 TDI plus, Audi R18 TDI, and Audi R18 e-tron quattro — burned diesel on the way to first place.
Diesel does get more fuel economy than gasoline, and not by a slim margin. Diesel is more than 33% more efficient than gasoline is when it comes to your fuel mileage. This means if you were to get for example, 30 miles to the gallon, a diesel equivalent engine would get 40 miles per gallon. Diesel needs to be run through a diesel engine, and diesel engines offer more torque than a gasoline engine. Torque allows for great acceleration, which also accounts for the great fuel economy numbers.
Will there be further advancement, sure the Ford EcoBoost is an example guess what they did, direct injection (DI) to allow higher compression (10.5:1) with peek boost pressure of 11.6 psi the spray of gas helps cool the cylinder and reduce the effects of the extra boost. BTW this is what a DI diesel has been doing for years including the after-cooled turbo charging of the intake charge.
I am intrigued by Homogenous charged compression ignition ( HCCI) Look it up.
I would also like to see the octane in ETOH utilized more, a great deal of power can be found with high compression and high turbo boost as found in Indy cars. Ford is looking at a duel fuel experiment using 22+ PSI of boost and injecting E85 during high boost periods from a separate tank but reliability seems to be a problem right now.
Variable valve timing has been around and for the most part matured.
Start stop systems, 6+ speed transmissions, variable displacement engines (4-6-8) has been done and helps a small bit at the expense of complexity. However these can also be applied to any diesel engine so not any real gas advantage.
Yes it seems a bit of reading IS in order.