I have 6.2 with cat exhaust(2014) and was wondering if it is true that the hp...320... Did not change from the previous engines with normal exhaust. Anyone ever test this?

hopefolly bup will see this,he will know.

The hp did not change. They are still making their rated hp

The HP is the same. also believe it or not many of the small blocks actually picked up a tad of HP because of the 4 - O2 sensors installed - 2 pre cat and 2 post cat per side. This helped with better fuel trim hence the tad bit of HP increase. I head from 2 to 7 hp in some models depending.

The comparison is between same models against same models NON cat engines vs cats / O2 sensor engines / newer PCM / ECM 09 and the latest version.

Also the ECM / PCM O9 the newer ECM / PCM 's have come along way from past ECM - MEFI's 1234 and the ECM / PCM triple nickel.