Uh-Oh, something is wrong!

[Scrappy]

I dynoed my truck again today and something isn't right. I dynoed in Feb and put down 457/ 1002 on 5/5 and the VA 0n 100%. Today on the same settings it was all it could do to put down 394. 2 and 900 ft/lbs. It would pull real hard to 2000 rpms and fall on its face. Anybody know what is wrong? Ideas?

 

[Mad Bomber]

Too many varables to list, differant dyno, how hot it was cooler air = better #'s

 

[Scrappy]

It might be the tires I am running now compared to before (35 BFG M/T's to Toyo M/T's) it is warmer and more humid today though.

 

[KYOUNG]

depends on who calibrated the dyno!?

 

[Scrappy]

it was Floor it's dyno. The numbers weren't too far out of line but I am worried as to why it pulls hard to about 2G's and then drops off. I guess the Holley Blue ain't cutting it anymore!

 

[Beach]

Air/fuel filter's, could be dirty limiting fuel when you get into it?

 

[cj hall]

hp falling off

try changing the fuel filter sounds like it's pluged

 

[CATCRACKER]

rail limiting valve bad maybe? You can plug it off to see if that is it... have not done this but more qualified members will chime in.

 

[Scrappy]

I changed the FF after we got home and it seemed to help slightly but still falls off, it smokes up to about 2K then clears up. I also checked the rail valve , it seems good since it is not bypassing any fuel with the banjo bolt removed but there is some fuel coming from the return line @ the rail valve( coming from the CP3/injectors)how much fuel is supposed to be returning to the tank? do I have a injector bypassing back to the tank thereby killing my rail pressure?