Nismo87SE

Okay not to beat a dead horse or anything but the Socal guys provided some facts to back up their claim that the SI is better than a CAI. They measured the MAF voltage via Techtom mdm-100 on a CAI and SI car, both had the same mods minus the intakes. They also found a scientific theory or explainion that shows that the CAI with more tubing will have less air velocity compared to the SI. Of course we (CAI equiped) counter by saying the air is denser thus packing more o2 than the SI. They (SI guys) counter by saying the difference in temp isn't as big as we (CAI) believe it is. Also the SI does have a higher MAF voltage though. But here is the kicker. In the 1991 300zx FSM I borrowed it says Also in the FSM the MAF has 2 leads going into the ECU, I'm sure one is for the voltage to the maf for the hot film. Here is the thing does the CAI's tubing from the MAF to the TB flow better or worse than the stock piping? The SI uses stock piping from the MAF to the TB. Which means that the velocity won't be as constant as the CAI's will be after the MAF. So again without flow testing the stock tubing vs the CAI's we don't really know if the SI does or doesn't suffer from the same lower velocity. Now if the MAF reads X amount of voltage and sends Y amount fuel everything is okay. But if you have less air that has been already metered by the MAF it means a richer mixture. I know for a fact that when I put my cone filter on my MAF my car was running rich. How did I know this, well according to my FSM I checked my o2 sensor monitor in a mode II test. According to my ECU in closed loop, the ratio that the ECU had to use to keep the mixture within the 5% rich/lean window. Was more than 5% lean, thus my car in closed loop with the cone filter on the MAF was running richer in closed loop. What does this mean in open loop? Well in open loop the ECU doesn't read the o2 sensor, it basically has a chart of probably rpm vs MAF figures. So it injects the predetermined amount of fuel programmed by nissan. Which means that after the air has flowed past the MAF, sudden changes in velocity (slower velocity) would cause a richer mixture. So I leaned out my mixture in closed loop via my adjustable MAF. Here is an idea. Why not try the MAF to cone tubing from a CAI, but keep the TB to MAF tubing stock? This would eliminate any differences in flow behind the MAF. My CAI is ran this way and on the dyno and at the strip I proved my 11hp gain. Not only did I get lower ET's but I have higher trapspeeds. Even when I was hot lapping my worst time was better than my best time with the cone filter on my MAF. BTW I find it hard to believe that the CAS (crank angle sensor) cannot be adjusted to advance or retard ignition timing. Now in the FSM for the Z32 there is a certain procedure that has to be done to get to the base timing mode for the ignition. Because if you don't adjust the basing timing, anyother adjustments will be overwritten.