How do I fix nitrous that runs too rich?

[NOSstang89]

I finally finished re-installing my NOS Big Shot today and I took it out for a spin to see how it worked. The electical problem that I was having is fixed, but now it runs way too rich instead of lean like it used to. I had some buddies following me just in case something happened, and when I hit the spray, the car bucked like crazy and the motor was popping, and my friends told me that there was tons of black smoke coming out of the tailpipes.

Since it was running lean before, I upgraded to a 255 lph in-tank pump. Timing was at 7 degrees (just to be safe -- I run 21 normally). My spark plugs are gapped at .038" and I run 93 octane. Fuel pressure is at 38psi and the kit is set at 150 hp, and I checked the jets and they are correct. Where do I go from here? Thanks!

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'92LX hatch, 302 w/TFS Street Heats, Performer RPM intake, Crane cam .499/.510, Crower 1.6rr, 70mmTB/EGR, Pro-M 75mm Maf, SVO 30lb injectors, BBK underdrive pullies, 255lph intank pump, BBK short headers, MAC 2.5" off road X pipe, FMS King Cobra clutch, 3.73 gears, SVO upper arms, HPM Megabite Jr. lowers, Moser forged axles, lakewood driveshaft loop, air pump removed