If you have your MAF's in parallel (one on each bank) you need to add the signals, not average. If you average it you are sending your ECU the signal equivalent to about half of your engine displacement
------------------------------------------------------------------ 1992 300ZX NA 5 Sp (Dead) 1990 300ZX NA Auto 2+2 (Dead) 1990 300ZX TT 5 Sp (Building) 2004 G35 Sport 6MT (DD)