A few questions

[thedieselguru]

I know that there are different calibrations for 250/350 and 450/550 trucks. Have any of you played around with the 450/550's much? What are you finding different about them? Are they different to tune or are the maps pretty similar?

Also, my work truck is a 97 F47 with a manual trans. It hits the scales for about 12k but the 4.63 gear gets it moving easily. Problem is, 9 mpg! 45mph is around 2000 and 70 is over 2600. What would be done in tuning to help mpg's? I'm working on getting the boss to turn over the funds for minotaur and use this truck for a learning project. Hope to be purchasing this month so I'm trying to get a feel for where to start.

Thanks
Roger

[cleatus12r]

I know that there are different calibrations for 250/350 and 450/550 trucks. Have any of you played around with the 450/550's much? What are you finding different about them? Are they different to tune or are the maps pretty similar? For the most part, they are very similar. On the other hand, the "big" trucks will be able to use the same tuning as the "small" trucks.

Also, my work truck is a 97 F47 with a manual trans. It hits the scales for about 12k but the 4.63 gear gets it moving easily. Problem is, 9 mpg! 45mph is around 2000 and 70 is over 2600. What would be done in tuning to help mpg's? I'm working on getting the boss to turn over the funds for minotaur and use this truck for a learning project. Hope to be purchasing this month so I'm trying to get a feel for where to start. 12K lbs. and 2600 RPM make for a very mileage-unfriendly situation. The best thing you could do is try to keep the RPM below 2100. Any real "tuning for economy" is going to be negated by those high RPMs.

Thanks
Roger

If you have any other questions or would like a more elaborate answer, feel free to ask.

[thedieselguru]

Yeah, that's kind of what I had expected. I goofed on the numbers. 50mph is 2000. 2100 is 55. I can't decide if I want to goto a 4.30 or all the way to 4.10. But again, I'd have to pry that money out of the bosses hands.

So not much changes on the 4 and 5's huh? I figured that would be the case. Years ago, at a class with ford I asked an engineer about it. He gave the standard "they are different because they are used differently" answer. But no details from him or anyone else I knew. I always thought the fueling curve might be a little steeper down low for the heavier loads. Because I have seen the VFDES rates differ between the big and small trucks at boost less than 10 psi. VFD made more sence to me because it follows cm3/stroke the way injection pump test specs are writen.

Anywho. kinda got rambling there.
Thanks
Roger