Boost Bottle de-mystified
Hi Fetor, I cannot completely understand why you would refer me, and the other 4-stroke Whizzer guys to 6 pages of back and forth 2-stroke chatter with very little scientific information.
If you had read this stuff, one thing came out in the first page that the boost bottle PROBABLY (read WON'T) work on a reed-valve engine.
When I had high interest in performance on the little chinese engines, I did some research on boost bottle technology, and here is the Reader's Digest Condensed version.
The total displacement of the boost bottle and it's lines and fittings, to be most efficient, should match EXACTLY the displacement of the engine. Ported into the intake, when the 2-stroke "sneezes" back into the carb, it would (presumably) "charge" the bottle with mixture, and upon intake, the contentents of the bottle would "push" a little, while being sucked back into the crankcase. This was thought to be a little like "supercharging" the crankcase. This system was credited to Yamaha Corp in the dissertations I read.
Ok, now if the reed (in between the engine and carb) would stop the action of the bottle, what do you think might happen with our intake valve? A good running 4-stroke will NEVER sneeze into the carb. We also do not charge our crankcases with mix to run, we port gas mix directly above the piston.
We concern ourselves with combustion chamber size and shape, cam profiles (lift and duration) carboration, cam and ignition timing, belt management, and other such issues.
In reality, there are very few simalarities in 2-strope and 4-stroke tuning and performance.
I hope what I've sadi here might clear up any confusion.