carbs
I have never used a predator, but I was at a dyno shop , a motor they were testing had a predator carb on it, they had hard time getting a stumble out of it at the crack of the throttle. They got it better, but they did put a "proven" ( carb from another motor that made good power) and it took care of the stumble, they ended up putting a 950 4150 base holley on it and it ran fine and made 39 more peak HP from the predator and 26 more than the "proven" holley. The motor was a street motor 468 in BBC full hydralic roller decent alum heads That all they wanted me to know ?
Not sure that helps, but Its what I saw.
I will say that dyno are very helpful, I have seen motor dynoes and chassis dynoes.