I ran the red on a motor with 427 HP & 425 tq. It fell on its face, every time at the track, As did the holley blue. Went to the mallory, and later to the holley black testing them, back to back at the track. I picked up 3 tenths & about 5mph. With the black & mallory over the red & blue pumps. They are not a good choice, in my opinion. Just based on my findings with my car. I have head of people getting away with using them. But for my application, they did not work. No matter what it says on paper, sometimes real world results are different.