patra_is_here Posted February 25, 2009 Report Share Posted February 25, 2009 (edited) If you are going to tune for performance, you are going to tune to 12.5 to 1 A/F ratio, at that point the 02 sensor A/F ratio is not used, there is absolutly no sense in spending money on 14.7 strategies is you want to build power a wideband o2 sensor will accurately read from 10:1 to 18:1 A/F well within the required A/F for EITHER peak TQ or peak HP Edited February 25, 2009 by patra_is_here Link to comment Share on other sites More sharing options...
Shelby Posted February 26, 2009 Report Share Posted February 26, 2009 narrow band 02's have been geting cars thru eminsion's testing for many years . i'l agree they are not top of the line these days but it's wrong to say they aren't acurate or just don't work , what is most times the fault is the meter use'd to monitor the 02,, all a/f meters are not equal by a long shot Link to comment Share on other sites More sharing options...
GCNTSi Posted February 26, 2009 Report Share Posted February 26, 2009 I will say that when I fuel pump filter was clogged the Autometer narrow band was not all the way in the green while I was at WOT, so it made me realize that something was wrong. It's a little light show most of the time but when at WOT it should be at full rich bar, or something is wrong. You can't do any real tuning with it but it does have some purpose, I think. -GCNTSi. Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted February 26, 2009 Report Share Posted February 26, 2009 (edited) sizing injectors, you use the heat temps to properly size your fuel injector. I cant help it if you insist on running MPI , but everything I said was correct, it answered the mans question about why his A/F gauge was acting like it should . MPI is superior in every aspect. His narrowband isn't acting like anything i've even seen on a properly running TBI 2.6L. Rich idling is the norm, cold or at operating temp. The only time the "light show" bounces back and forth is when you're cruising and the ECU is hunting for the optimum A/F for fuel economy. then you got into dyno tuning From a performance point of view, the fuel distribustion can be better understood by individual exhaust temp monitoring then by an average wide band reading in a single down tube ( if you want to stay with manual gauges) If you are going to tune for performance, you are going to tune to 12.5 to 1 A/F ratio, at that point the 02 sensor A/F ratio is not used, there is absolutly no sense in spending money on 14.7 strategies is you want to build power I would rather spend the money on injectors properly sized instead of sensors there are not useable EGT readings definitely complement A/F readings, there's no way i'm disputing that. However, given the last reply I made, there's no way in hell you can know if you're in the danger zone when it comes to the A/F. The EGT's will rise, both baseline and peak during repeated runs. Say you make a mental note on a dyno with a sniffer, that at 76* ambient temps, and 18psi, your 1550* EGT reading means your A/F is 11.8.. How do you know on the street what your A/F is when the temps climb to over 1600*? You would literally need to make up a spreadsheet with hundreds of plotted point to keep track of it all. Or, get a wideband and see the results in real time. And when your injectors or pump start to slowly fail, what does your EGT tell you? Nothing. You could attribute a 20*f rise to ambient temp changes, or perhaps it's something with your ignition. Whereas, the wideband will let you know right away that it's a fuel related issue. And I really hope you have some kind of meth or water injection if you plan to tune to 12.5 with FI during peak boost. I understand "lean is mean", but this isn't a NA pushrod V8. Edited February 26, 2009 by JustPaus_88TSi Link to comment Share on other sites More sharing options...
Recommended Posts