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Our first test pulls were with our ported Indy 2D dual-plane intake manifold. The 2D offered tremendous low-end torque, making 500 lb-ft of torque by 2,900 rpm, and holding above 500 lb-ft past 6,500 rpm. That's a broad power range! Peak torque came in at 5,300 rpm, recording 565 lb-ft, while horsepower reached a peak of 632 hp at 6,300 rpm. Compared to the best numbers we achieved with the hydraulic flat tappet and the two-plane, we were seeing a gain of 12 lb-ft of torque, and 72 hp when compared peak-to-peak. The roller's huge advantage in horsepower was in letting the engine keep pulling upstairs.