- Joined
- Feb 26, 2014
- Messages
- 252
Yeah, they were in Conshohoken, just a couple miles from where I lived. Stu
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Hobby Machinist's Supercharger
- Thread starter racecar builder
- Start date
- Joined
- Apr 23, 2018
- Messages
- 6,512
It's kind of hard to bolt a random supercharger on an engine all willy-nilly and expect to get it to idle, let alone handle transient throttle movements without things going boom somewhere. Knowing the displacement and drive ratio is just scratching the surface for balancing the thermodynamics and fuel/spark requirements of the system. A developed boost map (adiabatic efficiency from pressure ratios and volumetric performance) is the minimum info required to tune a forced induction system. You could put one of these on your riding lawn mower and tune it to run okay at one spot in the throttle's sweep by trial and error, but if you want to run that supercharger "wet" first invest in some kevlar undies to protect your peanuts!
Superchargers are sized based on the desired power output, not engine size. Figure out how much air you need to flow to produce the power you want and work backwards. You're just making a single stage air pump into a two stage air pump.
Something else to think about is the scalability of a positive displacement vane type compressor. I suspect the thing will end up being impractically large and heavy for what you'll end up with, not to mention using a lot of power to operate. The Judson and Shorrock blowers were only marginally effective in the late 50's and completely abandoned once cost effective turbochargers came onto the market in the early 60's. In fact this is about the only supercharger design I can think of that has never been used in an OEM automotive (or aircraft) application.
Not saying it wouldn't be an interesting project. Just not racecar parts.
Something else to think about is the scalability of a positive displacement vane type compressor. I suspect the thing will end up being impractically large and heavy for what you'll end up with, not to mention using a lot of power to operate. The Judson and Shorrock blowers were only marginally effective in the late 50's and completely abandoned once cost effective turbochargers came onto the market in the early 60's. In fact this is about the only supercharger design I can think of that has never been used in an OEM automotive (or aircraft) application.
Not saying it wouldn't be an interesting project. Just not racecar parts.