Quote: If you cap it off at the carb you could get a high speed miss. You can starve the engine for fuel at the top end.
The center carb external fuel bowl vent line nipple? The enclosed vent valve is closed off at any throttle position other than idle and off-idle. Plugging it off will have no effect high speed fuel mixtures. It is intended to be vented to the atmosphere if not plumbed to the breather cap or a charcoal canister however.
