WOW! Now I'm confused, :shock: I have a little BBC with 22PSI of boost. Should make about 1100HP on the small tune. I was told since, I'm going to take it to shows and drive it on the street mostly, that I needed 1 with a sprag. Then I explained that it would be taken down the track on some weekends and the story changed to a spragless. I have not broke down to buy 1 yet since my car is still a few months from completion. But I guess I better call TSI and ask some real pros about this 1.