First off, I have an 83 nissan 280zxt. I'm using the em4-6f system. I have rpm fuel values set at 82 after 4500rpm, yet the car still goes rich higher up in the rpm and it's not boost related. It will go rich slowly, but seems more like its a product of time rather than anything else. The longer I'm in a gear, ther richer it will end up before I shift. I'm using the innovate WB meter to verify this while tuning. Boost is a constant 18psi, but as the rpms climb the car goes rich. Could this have something to do with the motors lack of airflow? Maybe a need for portwork, upgraded cam, etc?
The basics of my motor are as follows: 2.8l inline 6. Custom intake manifold (J. Thagard's) and turbo header, masterpower T-70 turbo, forged internals, stock cam, light headwork, 1mm oversized exhaust valves, and then all the little things to go with that stuff.
All I can figure is that the car can't flow the air needed for the fuel being put into the motor at the upper rpm range. I even tried a new wb sensor just incase mine was messed up somehow. Any help is appreciated on this.
James Roraback