> i've heard of compound engines where the smaller combustion cylinder > exhausted into a larger cylinder for further expansion, but if they > really worked all that well we'd all have heard a lot about them. Actually compound engines work extremely well. They are very common designs of steam engines. I've never heard internal combustion engines being built that way, but I suppose they could. They would require a pretty strange looking block though as the usual rule is the low pressure cylinder has twice the diameter of the high pressure cylinder. Picture a four inch piston next to an eight inch piston! Cheers, Dave _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://splatter.wps.com/cgi-bin/mailman/listinfo/amc-list