So, I wanted to come back and revisit my observations. I didn't have much time last night.
1. The short tails made power. I don't know how much, but enough to make a notable difference and affect the gains of the corresponding mods.
2. The Nismo exhaust is very efficient. I did not see it as a restriction point after replacing it with the larger 2.5" AAM exhaust of the same design. There were no gains without tuning.
3. The Z1 intakes did not initially show a power increase, but the curve of the dyno adjust slightly at the top of the power band, indicating the car was breathing better. Again I saw that the stock intakes were not the restriction point to magically increase power
4. The AAM resonated test pipes increased torque by 2-3lbft and 1hp. This is within a margin of error. Again, I did not see a notable increase without tuning.
5. The AFR changes with an intake and exhaust were minimal. The AFR changes with the test pipes were notable until about 3500 rpm. The ECU did a fair job compensating for the changes. The ECU did not see to adjust magically to make power. It richened up the AFR. There is no flat spot above 6500 rpm, noting that that restriction no longer exists. Tuning on average made 9whp and 9lbft across the entire power band.
6. Tuning unlocked 12whp and 12lbft of tq. It wasn't until after tuning that power from the mods were showing. The AFR's were adjusted to around 13, fine for NA.
For reference, I added another dyno graph of a later pull on the same day as the tuning with identical conditions. The results are in STD.
