Keep in mind I am NOT going to try this but I was reading threads about the Mugen ECU and how it runs lean. Really lean. Someone posted that he upped his fuel pressure a little to richen things up a bit with the mugen ecu, I am guessing causing more fuel to come out of each pulse of the injector. His post said the ratio stayed in the safe zone after the adjustment.

So now you probably see the direction this is headed...........If the stock ecu runs rich for safety, and tuning computers and SAFC's and the like lean it out a bit to make more power, theoretically, could you just lower the fuel pressure a bit on a stock car to produce a few extra horsepower and still be safely rich? Maybe lower it by 2% or 5%?

I know that this approach is EXTREMELY crude, and would make the a blanket adjustment over the entire RPM range, but I was just curious.