Lots of things would need to be checked. But here's my math:Sure you could try 3600 in climb, that would get you 22.1hp not 32hp.

- A 22' span wing with 70 sq feet of area lifting a 7171lb airplane at 70 knots generates about 24.5 lbs of induced drag.

- A stopped 46" long two-blade prop with a AR of 8 has an equivalent flat plate area of .77 sft, and at 70 knots (SL) generates 13 lbs of drag.

- Profile drag: Roundabout method: The SD-1 requires about 12.84 HP for level flight at 70 knots, which is equal to about 64 lbs of thrust (at 70 knots). Subtracting the induced drag (19.4 lbs with this wing and weight) leaves 44.6 lbs of profile drag for the SD-1 at 70 knots. As you point out, the bluff tail end of our MicroMaster is likely to be draggier than empennage of the SD-1, so let's add 25% (a total WAG) to the profile drag, so we can expect about 56.5 lbs of profile drag.

Total drag of the Micromaster in level 70 knot flight with one stopped prop: 24.5 + 13 + 56= the 94 lbs total. That requires 18.8 effective HP at this speed, and if our prop is 75% efficient, it will require an engine output of 25 HP to maintain level flight. Each 100 FPM of climb at this weight requires 2.15 effective HP, or about 2.6 HP with our assumed 75% prop efficiency. So, if we've got a 28 HP engine (e.g. the 810 cc stock Vanguard as used by the Luciole in direct drive), we can generate about 100 FPM of climb. If the hopped-up Predator can give us 32 HP, then we'll see about 270 FPM of climb.

Lots of assumptions here that could work either way. The biggest ones are the prop efficiency, the profile drag of the MiniMaster, the real practical engine outputs. I've also assumed that climb occurs at 70 knots, if the wing performs better at 60 knots then all our profile drag numbers (incl the stopped prop drag) go down by 27%

__and__our thrust-per-HP goes up by about 8%, both of which translate into improved climb rates.

I share your skepticism. But the racing carts, racing mowers, mud-boat skippers, etc are undoubtedly producing a lot more HP than stock, so there's that.I don't believe claims of hop up sellers. :ermm:

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