The stock “beer barrel” intake runners are 15.5 inches long at the centerline of the runner. There is another 3 inches in the cylinder head for a total of 18.5 inches. This length tunes to resonance between 3200 and 3800 rpm. That matches the 5.2 but is not optimum for the 5.9 V8.

The 8L V10 has a 25 inch runner length and double resonates, first at 1750 rpm and then at 3200-3600 rpm.

The longest path of the variable 5.7 Hemi is about 27 inches.

Cutting back the beer barrel runners like the excellent pictures at utaperformance show will boost higher rpm torque and hp.

Me personally I thought about lengthening the beer barrel runners by adding 4” of aluminum tubing to move the entrances to the opposite side of the plenum, but the new 22.5 inch length would not move the resonance to the 1500 to 1800 rpm cruise range for better hill climbing.

I wish a V10 style manifold had been made for the 5.9 V8.