H2Odrx, Yes the rods can be shortened but only about 5 thousands. Typ4 (Russ) offset grouns his wrist pin bushing that amount to lower the compression on his motor. I sent him my custom made ball end mill for the precup chambers in the heads. They come really ruff so my thoughts were if they all had the same CC volume the motor would run smoother and better because its better balanced on the chamber volume. Using this and setting each piston at or near the same distance out of the block adds to this. Then balance the rotating parts and your efficiency goes up because if all things are equal each powerstroke of the pistons will make the same power and balance the power pulses to the carnk. Cylinder piston ring drag factors into this by each cylinder diameter too. A loose fitting piston ring set will produce a differant power pulse also but thats really splitting fine frog hair. Good readen huh.... Remember we only have 9 thousands clearance between the valves and the pistons during certain areas of crank - cam duration.