Why hasn't anybody ever looked into using an air-injected motor? The principle is very simple. Inject the fuel every stroke and also inject the air (under pressure) The exhaust gasses are forced out when the fresh air is injected. This way you can have a closed crankcase and eliminate burning the oil while every stroke is a power stroke. The only new parts would be the compressor and air-injection system. I would think emissions would be lower too.