Who cares how many megajoules is in it. Can you make power with it, and will it be cheaper than race gas? I want to test it myself this year, when you can finetune your a/f's for it and kick up the timing from the higher octane, it sounds like a possible winner in my book. Plus it's subsidized by the state or some farmer group, so the price ain't bad. Let's get some actual numbers from it instead of quoting internet sources with no real info.
Oh and back to the original topic. If you want LOTS of info on stroking, trying a google search on that word.
