I had the same plan, though not for the same reason.
I was working on 6.5 cc MB40-engines for F3D model airplanes. The fuel tank position in the fuselage of these little planes is critical as they pull a lot of g's in corners (we don't know how many g's exactly because the g-sensor's maximum is 'only' 36 g). When the fuel level drops, the mixture strength changes; not nice.
My plan was to replace the cruel fuel system (fuel in a bladder with exhaust pipe pressure squeezing the bladder from the outside) with a pump injection. It had to be constant flow because I could not find injectors capable of delivering the required tiny amounts of fuel to a 36,000 rpm engine.
I found suitable pumps here: h
ttp://shopping.netsuite.com/app/site/site.nl?alias=flightworks . These pumps are designed for model jet turbines but the snag is that the DC pump motors cannot run slowly enough for a small piston engine; the pump would drown the engine at the first start attempt.
Stepper motors were considered but the problem with those would be that when rapid pump acceleration is required, the stepper motor may miss steps and the engine will lean out without any feedback other than a complete cut-out because of a molten glow plug.
Pulse width modulation for the original DC pump motor was considered next, but then other things took priority so the idea never got finished.
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