(Side note: Darius must of thought you had a rb25 with sidefed injectors that are held down by caps and screws, instead a 20 just pushes the injectors in with O-rings)
Yea, compression test the motor. A buddy's 25 was idling fine, drove nice, ran super rich, fouled plugs constantly, didn't build boost... ended up being having bad compression on #5. Didn't tear it down yet but it took 15mins to find the problem.
