doesn't need to be spooled like a turbo
Can't be spooled like a turbo, once your pulley sizes are fixed you're left with whatever stall speed your engine makes. If it won't launch, you need to turn it faster and reach serious boost within your stall speed, a looser converter, or re-purpose the engine for better lower end torque (earlier intake closing, more static CR).
AFAIK the biggest complaint to the ATI is that most brackets are nowhere near stiff enough. The attachment points are limited to the nose of the engine, but the wide span between the pulleys is bad. The brackets look big enough, but the force on them bends both pulleys forward. It's enough to slip and mis-align them. In some cases a simple doubler plate added to the mid-span (someone on Yellow Bullet said "I use a section of angle iron") by rivets, screws (welding not needed) helps a great deal. Remember: aluminum is only about 1/3 the stiffness of mild steel, strength is not the problem.
Oh, I know how they work. I know they are fixed pully like a roots, they work like a turbo though in that they are a mechanical driven vane pump.
The converter plays a huge role with a roots, turbo, or just NA.
What I mean by my statement was the boost can be controlled like a turbo because they are compressing air. You can control when and how much boost they provide, whereas with a roots blower fuel is "usually" injected into the top of the blower mainly for cooling effect.
Not a Procharger expert by any means, but I have discussed with several who run them and have done some research.
I still like the old standard though by far the least maintenance of the 2.
Dave
