I have found that the key to reliable performance is moderation[sm=49_49.gif]. I forgot to mention that I did do some polishing inside the crankshaft, not grinding just polishing. The only mods to the case was to take away the blockages left over from the machining process and blending the transition to the ports, the ports themselves were only given a mild polish without altering their shape or volume. The port opening in the crank was left as is with just a very minor radius to the inside of the port. I did a very small amount of work and feel the results were spectacular. I have a few more racer tricks up my sleeve, speaking of sleeves I did not touch the liner At All! I was much too worried about peeling the coating and ruining a great running engine. 11,700 on a MA 11X6 prop is worth 5.72 lbs thrust on my static thrust computer, that is compared to the 5.32 the LA made. The results were more visible with the bigger prop. I also tried a 10X6 MA and got only .22 lbs higher thrust over the OS. I think these engines are both made to take advantage of the torque and therefore swinging a big prop they show a lot more power than trying to spin a smaller one at higher revs. The intake can only draw in so much air and I am sure both these engines use the same carb as a similar .40 size engine. (but there are ways around that too, I will keep you posted) Let me reaffirm! I am not Bashing OS! I think if the same mods were made to my LA the results would be similar! I just needed a top quality benchmark to compare my mods to.