Would there be, or is there a way to add a turbo kit onto these 70/80cc engines or would I have to fabricate one myself. Any tips?
Turbo a happy-time 2-stroke? Nope, won't work.
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Turbo a ~50cc 4-stroke engine?
Would work,
if you had a turbo small enough.
Nobody makes them.
You might be able to make something workable yourself, if you have access to a milling machine and a lathe. McMaster-Carr sells smaller chunks of the metal you need for the spinning parts. My main questions would be what to use for bearings? I would look for some open-cage ceramic bearings, and then expect to use an electric pump and radiator to circulate cooling oil through them.
I would suggest a supercharger instead, though. A centrifugal-flow supercharger would be about half-easier to build than a turbo would. Setting up the flow/boost is far easier also, as it's just mechanically driven off the crankshaft.
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I read the thread on the turbocharged Whizzer. I would wonder what that turbo is sized for. Turbos are driven by exhaust flow, so putting a turbo for a big engine onto a smaller engine doesn't work well, and may not provide any boost at all.
[edit] And what what he doing for bearing cooling?
The smallest turbos I found online were for ~500cc motorcycle engines. There's no way a 138cc Whizzer engine is going to get more than a couple PSI of boost from such a turbo, the Whizzer engine doesn't seem to me that it would provide enough exhaust flow to run the turbo very fast.
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