How are you determining the afr? That is the only down fall I see. It would be way easy to lean out of you dont have a wideband to constently monitor the afr.

 

That is exactly how I had mine setup. Fortunately my high N/A maf readings didn't overlap my low N2O maf readings so I could tune seperate fueling and timing for each. I did have to move teh MAF farther upstream in the intake track to get it to read the nitorus correctly without freezing.

 

I have a wideband. I would definetly not recommend this setup what-so-ever without one...

The MVolt targets do not even come close...
The PE Mult formula (14.7/PE=AFR) is completely off, even with inline trims.

Nor mine... On spray they hit 1.20 G/CYL
Plenty of gap to set 2 different timing curves seeing as I'm at .76 all-motor.

If I go back, this is what I will also do. Then, plumb the nozzle way forward of the MAF. The ZEX cone must pump so N2O in the air stream... I had 9'' away and it still froze it.

 

What jets are you running? I froze mine also with a AEM filter, which is about twice as long as that one, but I had a "jet error", which equated out to a 150 shot. With the 100 shot it was fine, and pushed my slow as pig to a 13.43 from a best of 14.5x off the spray. I ran great like that. I think that air filter is just too short. I also had a NOS brand fogger "Fan Nozzle", so I'm not sure what type or style of nozzle you are running. I'm not sure I'd run that DRY without a MAF, tuned or not.

 

I'm using a .050 jet. Put me from a 14.3 to a 12.9.

Could you explain why?

 

I understand that you have a wideband, but are you able to monitor it the entire run? Also, are you using a window switch, a button, throttle accuated switch? Just wondering if you are spraying all the way thru or what. I would expect it would be "loaded up" after the burnout while staged as well. I don't know, I liked my dry shot with the MAF and had great results with it, but just wouldn't feel safe without it. I understand the the MAF is basically reading the air and relaying that info to the computer, and you have by passed that step, kinda like a short-cut. It's just something I wouldn't be comfortable with, no matter WHO was tuning it. I'm not doubting your tuning skills, but that was a HUGE gain for only 100 shot, the kind of gain you would see from running lean, on the edge. Then again, I still have all of my Torque Management in, so you can tell I don't "push it". 1 1/2 second drop in E.T. from a .050 jet is HUGE!

 

I went from a 14.3 @ 95 to a 12.96 @ 106 spraying thru the MAF and the nitrous was entered at the end of my CAI... The one sitting in the upper left corner of the 2nd picture.
The MAF was pretty messed up after this pass.
Here is a log from the run before.


I made 3 passes. Each one, dropping the 60' a tenth and gaining no ET. Probably the MAF but, who is to say? LOL
The MAF wires were pretty bent up. I received an email from a guy who said this is what happens when a frozen wire 'defrosts'. I don't know how true this is but, the wires were definetly bent.

With the new setup, I'm bypassing the MAF altogether and spraying right at the Throttle body. The ZEX cone uses no nozzle so, your basically connecting a line to it with a jet stuck in there.
Oh, and I'm spraying thru the shifts.

 

Those o2's on the log there look very bad. It's kinda small, so hard to see detail, but they don't look at all ideal!

 

The MAF was definetly injured at this point.
Timing, MAF output, O2 readings, and the IDC were all over the place.

 

o2 readings are a direct result of the 02's. The MAF won't have much to do with them.