Kyle, all good questions... and I don't have direct answers for them.

What these occasional discussions always illustrate is that there are a lot of ways to build satisfying motors, and that every expert has evolved his own systems that work for him. There is no one best way -- which actually goes back to the original question in this thread.

Every motor is full of compromises; it's the nature of internal combustion engines, from the factory as well as modified, old and new.

My motor was designed by a Swedish builder who has done nothing for 25 years but build Volvo high-performance motors, pushrod, OHC, NA and turbo, street motors, race motors of all sorts. I had a specific set of requirements and a certain budget to work with -- and cost is always a factor. It meets or exceeds all those requirements, and didn't end up costing too much more than the initial budget. I could have spent more improving one area and less improving another -- which ones give the most bang for the buck to meet my particular requirements was my expert's decision. Other experts would make those decisions differently, no doubt about it.

My guy says the M rods are stronger and worth the weight penalty; Paul says they're weaker and puts more emphasis on weight to begin with. I don't know about the strength one way or the other.

I'm sure Paul builds fine motors and I know he's put a whole lot of work into development and testing. John Parker builds motors that are entirely different again. Parts that work perfectly in my design wouldn't be at all right in one of Paul's or John's motors. It's how it all works as a system, as you know.

Where this gets silly is when someone makes specific recommendations about someone else's motor, without really understanding what the system theory is behind it, what the specifics of the head work are, etc. It just doesn't work that way. You gotta pick one expert per motor, and ignore what anyone else says until that one's done.

--Phil