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I've played with different cam timing on both intake and exhaust side. There was little to be gain on the exhaust side, but the intake cam advance always gained midrange and low end power with lowering the rpms where peak hp/tq was made. And retarding intake cam always opposite. Retarding the cam will produce higher peak hp #s at higher rpms, unless you were hitting rev limiter or to rev to the higher rpms would requier stiffer springs which would cause some power loss. From everything I've read and did to my bike, it gave me better mpg with smaller intake cam that was advanced since the bike would stay at 60mph or so on the highway with less throttle open than engine with longer duration cam that was retarded which would requier more throttle to stay at that same speed. Retarded intake cam would also produce higher peak hp but peaky power band, and advanced intake cam would produce lower peak #s at lower rpm but broader powerband. Also in many books that I read it says that anything over 14 static comp would return very little power gains probably due to pumping loses, but by retarding the cam and lowering dynamic compression you could still use pump gas with stock ignition timing table.
BTW my next step it to turbocharge 14to1 engine, but use e85 since I don't think the engine would live on pump gas unless the ignition timing wlll get retarded to the point of very little power gain. But we will see.
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