If your carb is tuned to a restrictive air filter, and removing the air cleaner affects idle or overall performance, you might have to rejet a little. One of these little babies actually helped me with a carb issue on my fiance's car. I rebuilt the holley that was on it, and no matter what I did, it went rich after ptting the air cleaner on. So I bought her one the K&N's to fit the stock snorkle air cleaner and wella, all better.