http://forum.haxeflixel.com/topic/314/high-flxg-updateframerate-with-low-flxg-drawframerate-doesn-t-seem-to-work

PlayState.hx

package;

import flixel.FlxG;
import flixel.FlxSprite;
import flixel.FlxState;
import flixel.math.FlxPoint;

class PlayState extends FlxState {
	public static inline var SPEED = 1000;
	
	public var sprite:FlxSprite;
	public var switchFramerate:Bool = true;
	
	override public function create() {
		sprite = new FlxSprite();
		sprite.makeGraphic(50, 50);
		sprite.screenCenter();
		sprite.maxVelocity.set(100, 100);
		add(sprite);
		
		FlxG.drawFramerate = 10;
		
		FlxG.watch.add(this, "switchFramerate");
		FlxG.watch.add(FlxG, "fixedTimestep");
		FlxG.watch.add(FlxG, "elapsed");
		FlxG.watch.add(FlxG, "drawFramerate");
		FlxG.watch.add(sprite, "x", "x");
		FlxG.watch.add(sprite, "y", "y");
	}
	
	override public function update(elapsed:Float) {
		super.update(elapsed);
		if (FlxG.keys.justPressed.SPACE)
			FlxG.fixedTimestep = !FlxG.fixedTimestep;
		if (FlxG.keys.justPressed.ENTER) {
			switchFramerate = !switchFramerate;
			if (!switchFramerate)
				FlxG.drawFramerate = 60;
		}
		
		if (FlxG.keys.pressed.A)
			sprite.velocity.x = -SPEED;
		if (FlxG.keys.pressed.D)
			sprite.velocity.x = SPEED;
		if (FlxG.keys.pressed.W)
			sprite.velocity.y = -SPEED;
		if (FlxG.keys.pressed.S)
			sprite.velocity.y = SPEED;
		if (!FlxG.keys.anyPressed(["A", "D", "W", "S"]))
			sprite.velocity.set();
		
		if (switchFramerate && sprite.velocity.equals(FlxPoint.weak())) {
			FlxG.drawFramerate = 10;
		}
		else FlxG.drawFramerate = 60;
		
		FlxG.watch.addQuick("updateFramerate", 1 / FlxG.elapsed);
	}
	
}