HP question on a Cummins 8.3

[LongWeekends]

So our DP sold and we are shopping for our "upgrade". Engine size is one of the things we want to improve. I see the following in an ad:

"THE 8.3 LITER CUMMINS 360 HP ENGINE HAS BEEN RE-RATED TO 425 HP AND GETS 2 MPG BETTER FUEL ECONOMY. "

Can anyone shed some light on this? What is done to magically change the HP other than some creative typing?

As always, thanks in advance.

[Ivylog]

If you want 425 HP, look for the 8.9L ISL. Without changing the injectors and the turbo a 8.3 is already pushing it's max at 360. In PU's much of the mileage increase by a chip is done by increasing the tire size in the computer... making it LOOK like you've gone more miles than actual.

[Passin_Thru]

I have an Edge on a Duramax, increased by 40 hp and fuel mileage went from 13.5 ety to 17-19 ety and 10.8 loaded at 67 MPH and GVW 20000 lb.

[Tom_Barb]

LongWeekends wrote:
So our DP sold and we are shopping for our "upgrade". Engine size is one of the things we want to improve. I see the following in an ad:

"THE 8.3 LITER CUMMINS 360 HP ENGINE HAS BEEN RE-RATED TO 425 HP AND GETS 2 MPG BETTER FUEL ECONOMY. "

Can anyone shed some light on this? What is done to magically change the HP other than some creative typing?

As always, thanks in advance.

More than likely, a "BANKS" programer, that changed the fuel schedule to allow lower fuel flow at low power settings, and more fuel flow at max power.

[Executive45]

I'm sure they added a "chip" to increase HP. On my ISM, which is rated at 500HP the chip increased the HP to just a tad over 525HP. Did it change anything..? Well it lightened my wallet a bit but no noticeable change in power or mileage....Dennis