I was recently looking around on the net for some good material discussing hp vs. torque. Its pretty hard to find good material of this sort on the net that takes a person from the simple to relative complexity.
I found a very good article that discusses many of the issues that effect the performance of engines and explains the differences between engine types. The article was orignally written to prove/disprove the worthiness of auto engines as aviation powerunits. What resulted was an excellent overview of engine theory. Had this author explored crank/cylinder arrangement and rod ratio, this would be a wonderful article.
This article is the kind of stuff that you print off and read over a period of time, one reading just isn't enough to digest all the info - or at least for me it isn't.
hope you fellas enjoy it!
http://www.eaa1000.av.org/technicl/engemp/engemp1.htm Hudson