| Not bad actually. :) It is apparent that your fuel mixture is a good bit over-rich from 3000RPM to 7000RPM. Did you go through the 6 P's testing before taking the car to the dyno? And even moreso, did you go through the dyno dissertation? If not, here's the links: 6 P's:
[ http://twinturbo.net/net/viewmsg.aspx?forum=technical&msg_id=922678 ] Dyno Dissertation:
[ http://twinturbo.net/nissan/300zx/forums/technical/view/942535/The-Ultimate-Dyno-Dissertation-v11-revised.html ] The Dyno Dissertation is comprehensive - it includes the 6 P's. You can skip the 6 P's and get right to the guts of the matter. Looking at your dyno results I am impressed but I also see a good bit of room for improvement. Through the midrange, around 4KRPM to 6KRPM, the mixture is excessively rich and hurting performance more than any benefit of safety amounts to. If you haven't gone through the 6 P's or DD, this may be the reason for the results we see. If you have ensured that everything is spot-on according to those tests, there is a decent margin for improvement you can realize by bringing the mix back up to the ~11.5:1 ratio. I caution anyone in using an AFC to achieve this though. The problem with AFC's is that they intercept and manipulate the MAS signal to achieve desired fuel delivery results. The one thing, and most important, is that Apexi doesn't tell you that manipulation of the MAS signal also affects the ignition timing curve. Unless you were to use a Conzult, N-probe, Datascan, Blazt, etc, to monitor the ignition timing through the RPM band, you would not see the effect I am speaking of. Consider this for a moment: Your fuel mixture goes over-rich from 4K to redline. If you used an AFC to correct this, the device would reduce the MAS voltage signal through this RPM band to "trick" the ECU into thinking less air was entering the engine and cause it to deliver less fuel to achieve the desired result. But the thing Apexi doesn't tell you is that the ECU also uses the MAS signal to determine what ignition timing to use. In effect, the more you "fix" your fuel curve, the more you screw up your timing curve. If your car is in optimal condition, 6 P's and DD addressed, you really should consider having your program optimized to address these issues. Any competent ECU-level tuner will be able to take your existing program and dyno results to produce a custom program which is tailored specifically to your Z's "trends". ECU-level tuning allows for descrete and independent manipulation of fuel delivery and timing advance. It is worlds apart from "AFC Tuning".... In addition, you stand to gain both increased perfornance and safety through upgrading your intercoolers. It has been found that at this power level, there are considerable gains to be had by upgrading from the stock units. Right now they are tied hand in hand with appropriate ECU tuning as your biggest bottleneck for optimal performance......
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