I have been breaking in my 18 cv-r with a quart of break in fuel and i have began tuning it. I have no control over my idling speed and the idle screw does nothing. The idle speed is so high when i let off my brakes the car goes an honest 15 mph. Can i do anything to the engine to get the idle speed lower???

-kyle

You need to check how far the throttle is closing. It may not be closing enough. Then you can adjust the idle mixture.