All engines suffer from stock cams. CIS-E if you can get it to behave itself will give you the fuel you need to run a 300hp turbo motor. But getting there and it staying there is what most people have to contend with.
Right now my 8v is built and should make more power, but even after swapping brains twice i still run very lean (great for power but bad for longevity of the motor.) So I been trying to get it tuned to stay in the comfortable fueling range.