Hey Wildsupra,
I have had too much experience with the ol cordias lol. I have had the same problems with a few of them in the past. I break the rev problem down into the following areas;
Incorrect connection of vacum lines and 'oneway' valves (technically they are actually restriction valves) I have the correct vacum lines setup diagram if you need it. It's also on the cordiapower site.
Incorrect Throttle Position Sensor setting. Not hard to fix.
Faulty knock control sensor, again not hard to fix. It's the most common problem with cordias, it's like you give it some revs and the sensor freaks cos it's sick and thinks 'oh no massif detonation!'
Rooted vacum advance on the distributor. Again no big deal.
Give me a pm if you want any more info as I have a fair bit of good info translated from the Jap factory manuals.