I've had my GEN II in my car for some time and just received a FAST wide band O2 sensor and started comparing numbers with my TECH1a.
First, let me explain my set up. I have an '85 Corvette with a '92 LT1 running off of an '89 computer. The reason for that is so that all of the functions in my dash would still operate. If I went with the newer computer, items like my fuel mileage and such wouldn't work properly. We wanted them to work. The distributor rotor is still there but instead of using the opti, I've put a crank trigger on the front of the crank pulley. I had a friend put together a chip for me and I know that it needs some tuning due to my specific set up. I'm running a Vortech V3 (T-Trim) supercharger with a Camaro (cable operated) 85mm throttle body in front of the supercharger. There are no butterflies in the original LT1 throttle body. We also eliminated the bypass setup on the supercharger since it doesn't see anything but vacuum at that point any more.
I have a GEN II unit to transfer the frequency signal from the LT1 MAF to the voltage signal for the computer. I am currently setting the main scale at -40%. Again, I know I need to go back into the chip. When I drive my car at cruise (65mph) the block learn shows 122, which appears good, but the wb02 shows that I'm cruising around at 12.5:1.
I had thought that the A/F ratio would be more like 13-14:1 at cruise. The fact that my block learn is steady at 122 tells me that the computer is happy with that ratio and is pulling just a little bit of fuel out, instead of trying to reach that leaner A/F ratio. Now, when I step on the throttle lightly, the A/F does go to 13-14:1 ratio and the BLM goes to 108-110. Does that sound like things are going opposite of what they should?
Signed "Confused at Cruise"