I went to LG Motorsports today with the hopes of getting different results, but they got basically the same readings.

Here's the first run again at RPM:

And these are the results from LGMotorsports (on the first graph, bottom reading is with TC unlocked, top is locked):

And another:


LG pretty much said the same thing (but for $85 instead of $25 at RPM): bad A/F ratio and it's going to cause problems. So I'm driving around babying it afraid to get into it at all.

<div class='quotetop'>QUOTE(farmtruc &#064; Jun 27 2006, 09&#58;45 AM) [snapback]56403[/snapback]</div>
For what it&#39;s worth, I never use my tail pipe a/f device because it&#39;s always a little off and isn&#39;t as consitant as the O2 bung reading.
I also found out on mine, that the dyno reads about .5 leaner than the street.
Bring it back down if you can&#39;t find a shop to dyno it and we&#39;lld double check it, but I&#39;m sure it&#39;s fine.
Also, you&#39;d be surprsed that GM doesn&#39;t allow their trucks to richen up until about 5K rpms, doh. If PE delay isn&#39;t turned off, which yours is, then most trucks will not richen up until the top of second gear.
I know the &#39;06&#39;s wont&#39; until about 4900rpms.

let me know,
allen
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I asked about doing it before the cats and they said it was such a small difference, it didn&#39;t matter. If it helps any it was a DynoJet 1 and they did the runs in 3rd gear. I know you&#39;re too thorough to miss anything Allen, so believe me, I don&#39;t think you "missed" anything. I&#39;m just not in the know enough on A/F ratios and stuff to know what to do, what to ask of them, etc.