Well actually the car has:
306 cubic inch crate engine
-Again, just 4 more cubes..irrelevant as far as making more power. The most you gain here is from freshly honed cylinders unless the pistons add a bunch of compression...but....
9.0:1 Compression Ratio
-Stock CR for '87+ engines
Forged Mahle Pistons
-Forged is good for reliability, but doesn't add power unless they add compression, but don't
E303 Camshaft
-Eh, slightly better than stock but is going to be better for torque than peak HP
Aluminum "X" Cylinder heads
-Decent, this is where any gains are going to be had, but needs more cam than an E303
Trick flow upper and lower intake with spacer
-Which one? Plus the spacer could help or hurt depending on the rest of the combo
70mm throttle and egr
-Again, could help or hurt depending on everything else. Bigger TB doesn't mean more airflow or more power
24lb injectors with 76mm mass air
-Without O2 sensors, this is just making you run richer
Bbk intake headers and pulleys h pipe
-Headers/H/pulleys are good for a few HP, but not loads