What's new with two-stroke engines?
 

This was taken off another forum I belong to. I was talking about how far diesels have progressed, and another forum member followed up with this:

Not just diesels, but gas also.

High-pressure direct injection and high-boost turbocharging may finally lead to two-stroke gasoline engines becoming practical since unburned fuel will not be sent down the exhaust. And if workable, eliminating valves from the head may permit variable compression ratio engines to finally become a reality.

The recently announced Lotus approach to achieve variable compression ratio using a two-stroke engine is incredibly simple compared to anything I’ve seen (and engineers have been trying for almost a century). I hope they can make it work so it becomes as common as variable valve timing – which also took a long time to perfect.

With DI, turbocharging, two-stroke, and variable compression future engines could become much smaller, lighter, more powerful, and more fuel efficient. Who knows, some day we may be able to run both gasoline and diesel in the same engine.

A clean-burning two-stroke car engine would be very cool. I saw a two-stroke RZ-350 on the road Saturday, and while I have a huge soft spot in my heart for those engines, they're nastier than lawn mowers and chainsaws.

So, to have a cleaner two-stroke would definitely get my attention. :cool:

I've always wondered why no one built a two-stroke gasoline engine like a two-stroke diesel.

http://people.bath.ac.uk/ccsshb/12cyl/

Very interesting stuff and pictures there. Largest engine in the world and very very efficient.

How about a nice 1100 2-stroke triple - http://www.motorcycledaily.com/22april09_1100cc2stroke.htm

DD74 - Great stuff - Thanks for posting. I'm a snowmobiler and the direct injection and turbo sleds are the newest, latest thing on the hill. All looked good until the EPA got involved.

The mapping systems that could finally pass EPA tests are so lean that one brand has had it's good name ruined with nothing but seized engines this year. These machines are known for a mid-throttle "bog", a sure sign of a lean condition. The ones smart enough to avoid the headaches are putting on after-market "power-commanders" and run a map richer than the factory settings......Hopefully this all gets sorted out in a year or two.......

Now, back to the garage to work on my old 750 Kawasaki 750 2-stroke triple.....

I remember Chrysler working on a 2 stroke, injected, etc. for auto use for several years in the 90's. Power and economy was fantastic.

I think they put some demos out for real life testing.

Couldn't meet increasing emissions standards, though.

5.5 million foot pounds of torque. Makes a top fuel dragster seem awful... weak.