6.4 intake is far superior and is better than 20hp. It switches from short ram to long ram, engine masters tested it and it was eye watering how good they work. Not sure it fits an older non VCT hemi though
The cars computer is pre VVT and pre split runner so there's no reason to even try to use the later intake.
I've got the Engine Masters DVR'd that compares the intakes, from memory the biggest difference was a broader and flatter torque curve and a gain of HP at a high rpm.
As already stated, I don't care about gaining every last bit of HP, it will have far more that it ever did in 2006 so the wife will be happy with it.
I have a truck split runner intake from the 2014 engine that the heads came off, eventually it will be sold as I have no use for it.
