Sort of. In that case loping is responsible for the dimming lights [adjusting the idle down to the point where it's just below the RPM that the engine can maintain smoothly]. With Webers, my car lopes pretty heavy if the idle is turned down to anything less than about 900 RPM, though it will stay running clear down to 500 RPM, where it lopes VERY heavy, and you can hear each individual cylinder fire in time.