AussieSteve
Active Member
I agree Mike, Ron, (al.Fisherman), has a performance increase with his home-made verson, but in general I've heard almost no positive reports of boost bottles, whereas tuned pipes are well and truly proven.
Boost bottle, (maybe) 1-2% perfomance increase if you're lucky, well tuned expansion chamber, about 5-10% improvement.
2-strokesreally do need a tuned pipe to run well and efficiently.
In my opinion, boost bottles are a bit of a novelty.
If they were worth the effort, every 'port-scavenged' performance two-stoke would be fitted with a boost bottle.
When Jap designers/manufacturers were looking for more power in the 70s, if they worked, boost bottles would have been standard on all performance 2-stroke engines.
(Expansion chambers were standard.)
I refer to the 70s, because that's where these engines belong, in terms of technology.
In terms of the original question, all said and done, it appears that a boost bottle does work, but nowhere near to the degree of an expansion chamber.
Boost bottle, (maybe) 1-2% perfomance increase if you're lucky, well tuned expansion chamber, about 5-10% improvement.
2-strokesreally do need a tuned pipe to run well and efficiently.
In my opinion, boost bottles are a bit of a novelty.
If they were worth the effort, every 'port-scavenged' performance two-stoke would be fitted with a boost bottle.
When Jap designers/manufacturers were looking for more power in the 70s, if they worked, boost bottles would have been standard on all performance 2-stroke engines.
(Expansion chambers were standard.)
I refer to the 70s, because that's where these engines belong, in terms of technology.
In terms of the original question, all said and done, it appears that a boost bottle does work, but nowhere near to the degree of an expansion chamber.
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