Well at the moment what we know "works" is to make the header inlet 100% of the Ex port effective window area and place this at 2* bore diameter
from the port.
Then a nozzle of 75% effective area at 1.25* to 1.5* bore from the piston that has a smooth transition from oval to round ( steps DONT work as well ).
And the floor of the transition should be co-linear with the duct entry angle.
These are the numbers that Neels used to make near on 10% more power in his very accurate RSW125 sim - I challenge anyone to find any other way of improving Jan Thiels RSA/RSW by
that sort of gain in power.
And exactly the same numbers I have dyno and sim proven in dozens of project engines.
Just yesterday I measured up an 04 Honda CR125, and it has a much smaller duct exit than its predecessors,the area % and the spigot transition shape are dead on the money.
It even has reverse staggered transfers like an Aprilia, so as this model was the only cable driven servo PV they made, its a no brainer that
a couple of these will be going onto an MC21 to make a 80Hp road rocket.
The next step is to construct a point graph of all the proven results and to mathematically relate the Blowdown to duct exit and header entry areas - Frits request is my command.
Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.
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