Thread: Xp owners, input please?

Yeah location-elevation, temp, humidity have a great deal to do with how the car runs and what you can sqeeze out of it. Your 02 numbers depend on what sensors you are using. I have found that most aftermarket replacement sensors read on the high side at WOT but OE or aftermarket arent the best thing to rely on for full throttle tuning and a wideband is the only accurate way to see what you have. I have found over the last few years of wideband tuning that typically stock GM 02 sensors until the 04-05 year range will read in the 885-905 range at 11.5:1 AFR and some aftermarket sensors will read in the 940-965 range at 11.5:1 AFR. What really adds to this is that during a quarter mile pull the stock narrowband numbers will drop even if the wideband is reading the same number the whole run. 920s was pretty much the rule of thumb to go by as a target number before guys started using widebands for tuning, so 940 could be a little on the rich side.

Yep I use the NGK-AFX. It is not the prettiest thing in the world but I bought it because a few guys on the HPT boards highly recommended it and one of them does OE computer tuning for GM iirc and said the NGK sensor was one of the most accurate. I also bought it because it is more of a portable type gauge than the 2 1/16 gauges and this is what I use when I tune cars. I have had this one for about a year and a half and has never given me a bit of problem and has a great price tag.