Afraid of needles ? Try injection. The most common problem on modified engines besides the lean/rich dilemma is the inadequate delivery rate of the injectors. I've bodged up a really cheap method of checking the actual dwell percentage (On/Off-time) of the injectors. So while you're trying to modify the ECU like a madman and it still won't go richer you should check the dwell. All you need is a 3V zener-diode and 1 kohms resistor. Shouldn't bust anyone's wallet. Put the ignition on, do a little cut on the insulation of the wires going to an injector, take the plug out from the injector, measure which one of the wires has 12V in it, put the end of the diode with the ring on the body to that wire, put the resistor in series with the diode, put the other end of the resistor on the other wire. Put measuring wires to both ends of the diode and insulate with tape. Put the plug back in. Measure the voltage on the wires with a voltage-meter set on DC. Now you have a clear indication of the Dwell percentage, if the voltage ever gets to 3V, you're out of luck and so are your injectors.

There are a few things you can do if you actually run out of delivery, either replace with bigger injectors or raise the injection pressure. Either way, the air-flow has to be re-calibrated. You can probably raise the fuel pressure to the nearhood of 4 bars, giving a new delivery rate of SQRT(4/3)*ex-delivery. However you may run into leakage problems or the injectors may be reluctant to open under such pressure. A 15% increase in delivery rate is quite realistic.