Can you explain how a boost bottle works? Iâ€™m considering installing one on my sled, but am not sure on what it does or how it works.
Ski-Doo calls it an “intake resonator”, but most of us call it a “boost bottle”. This is a small plastic bottle that connects the intake tract of the carburetors on a 2-stroke. It is used to improve low end and mid range power slightly by cleaning up the calibration. During the intake stroke the fuel/air charge is flowing into the engine. When the piston goes down and hits bottom dead center this flow is stopped you get a wave “reflection”, or bounce back. Instead of having this wave going back and forth over the needle jet bringing up extra fuel during each intake stroke, the “leftover” charge gets sucked into the next cylinder that opens up. End result is a cleaner and crisper throttle response and engine operation, and makes the carb calibration a bit more forgiving. The difference is subtle, yet it generally allows a leaner jetting calibration and overall crisper throttle response and cleaner operation.