Just had nitrous installed on my car couple weeks ago and had it tuned...its a 100 dry shot running into the stock airbox so my tuner had to add fuel in the pcm and said my on motor it would loose just a couple horse and run a little rich..Today I just finished installing long t headers and took off the cats(rear 02s deleted)..Car runs great half throttle,, wot it falls on its face and backfires in every gear...Im not spraying it at all...Im not gonna spray until it gets retuned...just wanted your opinions...Do you think its running to lean??? no codes at all.....Thanks