Enya 40x vs Enya SS40BB: Performance run

I noticed that I did not have many if any videos of these two engines. Yesterday I decided to take them out and do performance runs on each. The release to the market of these two engines is quite different. The 40X was reviewed in 1978 and the SS40BB around the 1987 time frame. The curious thing is that the 40X features a more modern single piece crankcase design as opposed to the two piece of the 40BB. The two piece crankcase is an older design seen in the late 70's-80's OS FSR series engines. Both engine turned the same 11x6 APC at nearly the same WOT RPM. Now I did not really lean either to optimum, but they were close. You can see the 40BB weighs in at 1 ounce less than the 40X.