Related Photo Galleries
We started fiddling with the 770 Holley we originally slapped on the motor. We emptied the fuel, cleaned it out, opened and closed the secondaries, and bolted it on for another try. It turns out that the secondaries were caught-up on a linkage and once we got the problem fixed, the motor ran through the rpm like a dream. How does 491 hp and 521 lb-ft of torque sound? A lot better than the 440 GMPP rates it!