sorry, I didn't notice your message.
If you add boost to a 3.5, it will probably be a fair bit faster than a 7700kv. You'd need a "castle link" and whatever software they use to update the Mamba's settings from your computer. I think castle calls boost "cheat mode"
I can't say I know anything about the Mamba line of ESCs. Capabilities, boost settings, etc., so I can't honestly tell you if it can even handle a 3.5. I'd look it up for you, but I find castle's website too painful to look at.
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