Ilmor's 5 stroke engine

Have you guys seen this? I guess the news was broken in 2009, but this is the first I heard about it.

5-Stroke Concept Engine Design and Development | Ilmor Engineering

All of these alternative engine designs have some great challenge to overcome, I see 2 problems with this one. 1: carbon and soot buildup in the middle cylinder. With no gas ever entering the cylinder, its bound to buildup someplace. 2: Heat. putting all that exhaust into another cylinder inside the block is going to be difficult to keep cool. Other than that, it seems like a good idea!

the 14:5 to 1 compression ratio seems unrealistic. I dont know why all of these alternative engines have to claim such outrageous things.

Glenn M

It doesn't quote a compression ratio of 14.5:1 .

That figure in the article is the overall expansion ratio. If you read the article it explains the difference.

This is really cool. I am glad to see somebody working to improve internal combusion engines, so we will have options other than electric/hybred cars in a few years.

Brian Stewart
Forgive my ignorance, but I could not see where/how the exhaust gases get expelled from the central low pressure cylinder... Am I missing something?