I know the SAFC very well. it alters the air meter reading to read higher or lower than actual, to trick the ecu into adjusting the fuel higher or lower. It has e.nough adjustment to blow the engine

I don't think you need more pump, and the walbro is so loud it has the nickname 'whinebro' on other forums. This pump will probably need to have a bigger regulator and larger return line.

I would try first adjusting the fuel pressure higher if you're lean. There is a tamper resistant torx screw in the fpr top. Clockwise is more pressure/righer.

The symtom of not enough pump is being unable to hold consistant fuel pressure under heavy load.

You'll need an EGT if you want to do any real tuning, don't rely on O2 sensor readings alone.

John C.