Fuel mileage sucks! Please help!

[Scottfunk]

1 hour ago, pepsi71ocean said:

This begs me the question of what rear do you have on this truck?  35's are fairly big, and no matter what if you have a 3.55 rear your gonna be  struggling with the load. 

I have regeared the pumpkins to 4.10. With the smaller tires I was right at 1860RPM at 70MPH and now with the 35's I'm closer to 1730 at 70. I'll probably step back down a size when I have to buy new rubber. 

 

2 hours ago, Mopar1973Man said:

Clue. More boost you see going down the road means typically your burning more fuel. I've got to ask what is your engine load and boost pressure like at highway speeds?

 

Boost you should be below 5 PSI for 65 MPH. Engine load should be around 20% or lower if possible. 

 

Injectors what are you running? What was the pop pressure at? How many miles on the injectors?

I'm between 7-9 PSI cruising at 70MPH depending on the grade of the road. Engine load jumps between 24 and 33. The injectors were just built earlier this month and are 50 horse injectors popped at 315.

 

Before I changed the tires I was having problems with high egt's. I was up around 840* at 70MPH. I chased down quite a few boost leaks and was able to get it down in the low 600's. There were still a couple minor leaks I knew about. After I changed to the bigger tires I was back up around 850* but after sealing up the compressor housing, intake plate, and grid heater housing I am back in the mid 600's. I will check the load numbers on the way home tonight.

 

What is the best way to dial back the timing a little for winterized fuel? Just bump it down a couple degrees across the equalizer or in the individual timing settings? I have not played around in the Quad custom tunes much but everytime I do it seems like I make it worse.

[Scottfunk]

OK I tried to take a screenshot on the way home but try that in rush hour traffic. Anyways, best I can tell cruising,70MPH, on flat ground my load% is 26. But oddly enough, sitting at a stop it's 12%. 7% idling in park. What gives?