Stock Narrowband O2's for tunning WOT

[rpmauto]

The narrowbands simply put "switch" they will go to 8-900mv at cruise, idle and so on. Yea 900 mv is richer than 800, but you cant tune wot with them by any means. They are constantly switching to provide the "stock" pcm the info it needs to maintain 14.7:1 afr on a "stock" engine. I would assume with the money you have in a 408, and you have efi-live that you wouldnt want to melt it down. Just put it on hold till you get a wideband.

If your tuner put you on a sd tune how come the maf is reporting data. It should be failed. (cant look at the tune on my phone)

[SRT10KLLR]

The build has been 3+ years in the making.

I looked at the tune to confirm and the MAF high/low frequency is set to 1(fail). It is still plugged in though as the IAT is in the same housing.

[joecar]

I see DTC P0103 which confirms you're running SD (i.e. in failed MAF mode).

[SRT10KLLR]

Well I did the unthinkable; I upped the shot to a 100. I went to a buddies house and we hooked up a fuel pressure gauge and wideband. Unfortunately the O2 sensor on the wideband was bad so I ended up just spraying it anyways to see if my fuel pump would be able to handle the additional hp. When the nitrous hits the pressure dips for a split second then recovers and reads normal(58 psi) for the rest of the run. The mv again were in the 900 range when spraying.

I ran it at the track with the 50 and it knocked .5 sec of my 1/4 and now the 100 knocked off a full second.

I went to a dyno to check the a/f but was out of nitrous. According to the wideband from the dyno I am in the 12.3 range NA so it looks like I am a little richer on the juice maybe a 12.1 or so.

Have to refill the bottle and try again.

Here is a log of todays N2O run and a NA run for reference.

[SRT10KLLR]

You can't see the dip on that run because it was at the track and it spun off the line. The window switch was set to activate the nitrous at 3000 rpm so when it spun it immediately started spraying.

On the run from yesterday I was on the street with street tires so I would not hit the nitrous until well into second gear so I would not spin. On this scan you can see the dip in the O2 sensors when the nitrous activates. I could see in on the fuel pressure gauge when it happened.

[WeathermanShawn]

Original OP's Question..can you use Stock NBs for Tuning WOT.

Fresh NB O2's..AFR both 12.62.

1. IAT 90F MV: 872-890




2. IAT 64F MV: 929-942



Conclusion: You can not use stock NB for Tuning WOT.

Screen-shots Added to Tuners Checklist: http://forum.efilive.com/showthread.php?16139-Mechanical-Issues-that-prevent-Good-Tuning

[SRT10KLLR]

OK. Finally had a chance to use a wideband and it read 9.9-10.4 A/F on the juice. I did not have a smaller jet so my buddy pulled some fuel out of my tune using the PE. I went to the track and logged one run on the N2O which is named Today. The other two were from checking the A/F with the WB and after the PE was adjusted. The WB is not in the log data though.