Just sold my 91 300Z NA, Had a Jim Wolf chip along with upgraded intake & exhaust, new cam/ported& polished. Didn't add alot until I updated to larger fuel injectors, then I could WAY tell the difference from stock to chipped, But gas mileage was around 10-12. Had to sell or I was going to lose my license soon; thats why I have a Pathy! Can have fun even going slow!