ORIGINAL: MJD
ORIGINAL: bob27s
you will be fine with the SS muffler and any of those props (except the 9.25 pitch as noted)
in fact, if you want something scarey, get the 8.5x7.25 prop

A little magic occurs.
Say what? For which motor? Seems light for the SJ50/SS combo. Looks like the right load factor for the .50V1 though. Whatchoo talkin' about this magic? Don't tease me like that!
I guess Bob didn't see this to reply but while in the pylon forums I found this posted by Bob27s.
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While breaking-in the early version of the SS-40 engines using the apc 8.5x7 props, quite by accident/luck we found that the SS-40 had a secondary sweet spot just over 20K rpm as well. The 8.5" props ended up working great for the sport class racing. Racing the SS combination you would use an APC 8.5x7 up to 8.5x7.5 pylon prop. Peak RPM is up around 20K on the ground. Find peak rpm, back off 600-800 from there, and go
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