turbo sizing

[Christopher Bruno]

> 
> A while ago there was a discussion here about turbocharging a
> two-stroke, and the general consensus was that it couldn't be done,
> or was very difficult, at least. So how is it done?
> 
> Stuart.

First off I want to say that I am admittedly no expert on 2 stroke
engines.  The only one I have ever owned was in my 175 Yamaha Enduro.
However, I am quite familiar with their operation I would would venture
to say that there is no reason why a 2 stroke couldn't be turbo'd or
supercharged.  I would agree that it would be more difficult to
achieve high levels of boost but providing that the reed valves are
stiff enough to counter the highest boost but not so stiff that they
won't open during the downstroke of the piston then you should achieve
some gains.  Granted, you will be likely to have a great deal more
of blowby into the exhaust if turboing a 2-stroke but it should work
to some degree.
	I would agree, though, that turboing or supercharging a 4-stroke
does make a little more sense and will make better gains (at least in
efficiency).

-- 
Christopher Bruno
Teradyne
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