Yes I know it can affect carburation, but my question was did someone noticed that engine runs richer after riseing and widening the exhaust port. If there are many people who noticed that then we can say it's very likely to happen, right?
edit: Ok thanks for the answer. Plug reading by reading the color of the insulator nose is wrong because it greatly depends of the plug heat range, also you can have almost same color with very broad jet range. I've proven that to myself with my previous engine.