My A/F is F'ed!
 

How's it going everyone?
I just dyno'd today using a dynojet here in St. Louis. I have a 2005 G35 revup engine. From what I've been reading, my hp/tq numbers look really good for being completely stock. My question is, there's no way my A/F can be correct is there? The shop guys were saying that if those numbers were correct, then I'd be pinging, and ofcourse I'm not. They were playing around with the A/F probe at the end of the tailpipes (they tried both sides), but this was the best they could do.

I just wanted to see if anyone else has ever dyno'd this lean in stock form. I only know of one dyno around here, but I think I'm going to need a second opinion before I start throwing my mods on.

http://www.dx4life.com/ant/images/stddyno.jpg

Thanks in advance,

Ant

Um, your AFR looks pretty normal for not having tuning

check this out

Pinging has to do with combustion chamber efficiency (350z is not bad),

timing,

octane,

.......


compression,

intake temperature....


basically those guys don't know what they're talking about or have not seen many 350z's

Also, their dyno sniffer might not be calibrated perfectly...

I appreciate your input Wired. From looking at your A/F, it doesn't look like I should be too worried about modding it. Anyone know any good UTEC tuners in the midwest?

tailpipe sniffers are about as reliable as a Yugo. If you have even 1 muffler or resonator in your entire exhaust system, the tailpipe sniffer will be way off

in your case, I'm not sure if you have stock cats on, or a resonator or muffler, but I'm assuming you do, and in doing so, I'm telling you to not even pay attention to the dyno wideband. I friggin hate people who tune via tailpipe sniffers...............

Hey Ant - those numbers are great! The A/F is typical for the 05' and '06 350Z and G35, and the tailpipe should be reasonably accurate (we commonly do both tailpipe for the dyno readout, and another meter in the header for tuning - 99% of the time they read similar, although the tailpipe reading may register 200-400rpm behind on the dyno graph).

Many people do an ECU Flash such as this one http://www.alteredatmosphere.com/mm5...y_Code=350Z_EM to bring the A/F's down to a more desirable point.

Hope this helps,

Thanks for the input everyone. After my mods, I'll think about a fuel controller.

Wired, so the HFCs leaned you out a little in the lower rpms? Then you probably gained a couple HP from it when you tuned. Is it loud?

your A/F looks good to me. If you were 15ish or over in the higher rpm, that'd be bad.