I have a comptech s/c and the 8psi pully w/ 550cc injectors and we were able to get the a/f ratio's almost perfect w/ VAFC.

 

The VAFC is controlling the 550's in one of my customers S2000 with ease. I had no problems with it. The car is making 335whp and is running a flat A/F of 11.5. I just think that if your above boost levels of around 8-9psi, your gonna need to look into other forms of engine management because theres no telling what the stock ecu is doing with the timing. Someone needs to "hack" a stock ecu and get the stock timing maps. If you could do that, you could have a better indication of whats going on. Its probably based on load, rpm, airflow, and some other parameters, but it would be helpful nonetheless.

 

Low and behold, my customer posts just before I do... Thanks Bob!