Engine/Transmission (1998.5 - 2002) power max on high

[pro99]

I T seems that my truck runs better in level 5&6 than on level 9 . It doesn’t have the drag program in it. I have proper fuel pressure running around 13 PSI at wot and you all can see what I have done to my truck …. What’s up with that??

 

[Hohn]

my guess...

I would venture to say that you are reaching your maximum air capacity at level 5 or 6. I would assume that even at 5 or 6 you are smoking seriously with DD3s installed.



Does your EGT go up from 5-6 when you set it on kill? Even an HX40 has a hard time delivering enough air for the amount of fuel that the Pmax/DD3 combo is capable of injecting!



One thing you might want to try is a timing box piggyback. With all that fuel, then engine needs a little more time to burn it all. It should help to lower EGT a little bit.



Before you spend the money on another box, I would check all the functionals, make sure your sensors are good and stuff like that.



My $0. 02



HOHN

 

[MikeR]

You say "it seems". Is that dyno proven or just a seat of the pants feeling?



My truck is set up exacty like yours and mine is definitely stronger fully cranked up to 9 as opposed to 5 and 6: monster DD inj, Pmax, HX40... but I have a DD True Torque timing box stacked ontop of my Pmax-drag version.

It didn't seem like the timing box made the difference in the kind of problem you see because I have loaned out my timing box and continued driving my truck with the Pmax on, and it doesn't fall on it's face beyond levels 5 and 6.



Maybe possibly a map sensor problem?

 

[BillGotthelf]

PROTURBO99- I am running something similiar to your setup (275 vs. DDIII's) My setup runs pretty stout and progressivly faster as I get to level 9. I am waiting on a set of DDIII's and ATS exhaust manifold this week. I do believe you may be reaching or surpassed the air that the HX40 will supply. I'll wait to see how mine runs but I see a hx50/55 in my future.