I hate to say it, but nothing is cut-and-dry with this. Like all things, you have to take a compromise. The SVT manifolds themselves are a compromise that allows good airflow velocity at low and high rpm.
I try to remember it this way. The small tubes will have a higher flow velocity into a given cylinder than a large tube. However, the small tube has more resistance to flow and will not allow the same volume into the cylinder as a large tube.
So you have to choose which area is important.
The SVT manifold should keep low end torque high and flow well enough at high rpm to keep the torque high there as well.
The 3L 01 plastic upper and lower manifolds are obviously larger, and will flow more air. However, there will be a loss of flow velocity at the low end and therefore will likely be a reduction in torque. On the other hand, the high rpm's should see more torque because of this.
I choose a wider flatter torque curve, so that is one reason why I am happy with the combination that I used.
warmonger
