Stock 6.0 is rated by ford as 325 HP and 570 ft. lbs. torque. Has anyone dyno'd to see what actually makes it to the rear wheels?

 

The numbers that I've seen in various magazines and from previous posts are in the neighborhood of 240-265 hp and 435-470 ft.lb of torque depending on the dyno used and the corrections. Others will chime in, but this is the general ballpark where they will fall into.
Is there any reason as to why you're asking the rear-wheel power numbers? I just figured I'd ask.

 

Just to make a comparison for to some aftermarket numbers after some tuning is done. There numbers where rear wheel numbers from a Dyno, so I wanted to verify exactly what the gains where..

 

One of the best resources for a comparison of tuners was the "6L Shootout". This shows how many models of tuners compared in terms of what they produced from what they claim. The 6L Shootout is a good resource.

 

Basically you get about a 15% loss between fly wheel Hp & Torque numbers and rear wheel Hp & Torque numbers. FYI Dyno numbers can be skewed based on who is running the dyno and how they are sampling.

 

All of the trucks will perform a little different. You should base line yours first and then add your power parts. Then you will really know.

 

I have a 04 PSD with MBRP turbo back, Airaid intake, custom SCT extream race tune, disconnected EGR, Throttle plate removed.

My dyno #'s were 374 RWHP and 530 RWT

 

530 Torque?? that's sounds kinda low for an extreme race tune on SCT - would've thought well over 600....

 

I second that! I've read many times that the extreme tunes by ID or LIPD are putting around 700 ft.lb of torque down. Heck, my towing file puts around 600 ft.lb of torque at the rear wheels according to the 6L Shootout.

 

I am not sure of John K. tranny setup or how it was dynod as there are many reasons and variables why the RWT not being higher, like was the converter (if auto) locked at dyno testing.

However generally from my understanding it's not unusual to see much more than 550ft-lbs rear wheel torque if the tranny is stock on dynos. One of the last 2 diesel power magazines has a write up for those interested.