Ok so we got the new carb in and on runs great header doesmt get red We did let it idle and warm up for 20-25 mins and it didnt glow like it did with the junk carb gave just a little throttle for few secs is when we seen it granite it was very hard to notice it unless you looked real close it did not get any brighter if this helps you a little more i wanta lean toward the hotter plug but then again maybe just maybe the air/fuel should be turned out very little ill wait to see what you say