it's all about the tuning, properly tuned, there is no reason a bpu+vpc should not beat a plain bpu.
regardless of the fuel controller, aem, fields, afc, vpc/gcc, you're still gonna have to tune it and that'll make the most difference.
regardless of the fuel controller, aem, fields, afc, vpc/gcc, you're still gonna have to tune it and that'll make the most difference.