Basically an FMU sucks because it tries to force more fuel through the stock fuel injectors. It raises the fuel pressure in response to boost level.

Fuel injectors are rated by how many cc of fuel they can flow in a minute. The stock injectors are rated for 240 cc/min. The way the ECU controls the injectors is by sending a signal called "duty cycle." Thsi is represented in a percentage. The higher the duty cycle, the longer the injector stays open.

If you increase the fuel pressure without changing the duty cycle, all you do is is try to force a little more fuel through the same sized injector that stays open for the same amount of time. It doesn't do much.

What you want to do, is get the duty cycle changed correctly. The stock injectors really can't flow enough, so you should step up to either 450 cc/min ones out of a turbo DSM or 440 cc/min RC Engineering pieces.

You will then need a means of tuning the duty cycle. ZDyne sells a fully programmable ECU similar to the AEM EMS or Hondata for the non-OBD cars (which yours is). This is the best option.

For a more reasonable price you can use an APEX'i S-AFC. Basically the way it works is it takes the signal that goes from the MAP sensor to the ECU and changes it. You don't change the stored settings in the ECU but you trick it into thinking there is more or less air going into the motor than there actually is. Normally when the ECU sees a signal that indicates boost it goes into a limp mode. If you set the S-AFC to -40% fuel trim across the board, it changes the signal to not actually look like boost. The ECU sees this signal and responds with a lower duty cycle than necessary. But the trick is that since you have higher flow injectors than stock, they effectively "multiply" the duty cycle back up to what is necessary.

It would also be a good idea to upgrade your fuel pump.