Stacking is when the incoming pressurized air is building up inside the top of manifold runners. That is why a higher roof or a high riser manifold have this to prevent mass volumes of air from backing up in the manifold.


The best solution is see how much you can port the runners, this may help this, but the real problem is the height of the main plenum from the TB.. Is basically to small/low. if you could raise the roof up that would fix this....I have some good data I could show you about this... maybe your other option is the buy a larger plenum manifold with slight larger runners than stock, so your low end you be real strong and powerful.