I dynoed my street car, and here is the setup - TOTALLY stock motor. Stock heads, stock cam, stock rockers, stock pistons, stock crank, stock rods. NEVER been apart - Yes, the heads have been on the car since 1988 when it was assembled by someone at Ford. The motor probably has 90,000 miles on it (Bought it used, the kid changed the gears, but never changed the speedo gear)
And a Turbo Technology Kit with a T04b (The BABY of all V-8 Turbos).
At 15psi on pump gas it made 471 Hp, 537lb Tq.
And I've probably put 10,000 miles on the turbo with no problems. After all, it is my daily driver.