Ernest, it looks like you spent a lot of time and research and hard work on those models, and it's helpful information.

Although, I am just going to say what many others are thinking in that these trucks are all different, and each is going to have slightly different HP and MPG numbers, no matter how many times you try and compare it to a standard model based on PSI and drag and wind resistance. Hand calculated numbers speak for themselves...gallons used and miles traveled. That gives us the MPG numbers we are looking for, and accurrately.

A person can try and explain just about anything using models and numbers, but many times it just doesn't work out that way. The world is made up with variables, millions of them at any given point in time. Why else would NASA, an organization made up of the most brilliant mathematical minds in the world, run into so many problems when they finally execture a mission into space? They've worked the numbers over hundreds of times...they know what is going to happen...at least, they think they do. Many times it just doesn't work out that way.

 

I got 21 mpg on my truck the day I bought it on the 7 hour drive home from the dealer. The entire time I was challenging myself to see how high I could get it. Normally I get about 13-14 though. I got 17 when I was towing a truck 5 hours, however that is probably due to the fact that I was trying to be more careful and I wasnt going as fast.

 

Excellent point, good post.
I laughed when I read BLAH BLAH BLAH, my eyes get crossed when I have to deal with numbers and spreadsheets too.

 

Since I used to be a support contractor for NASA in the 60's during the Mercury and Gemini days leading up to the first trip to the moon, and also did a little consulting work on the space station in the 90's before I retired 9 years ago, I've got a little insight into your statement about " NASA, an organization made up of the most brilliant mathematical minds in the world, run into so many problems when they finally execture a mission into space?". Well, a lot of their problems are management related, but the "most brilliant mathematical minds in the world" are sometimes lacking in common sense. I'll just point out one example, the Mars Lander that crashed because one group of mathematicians doing the orbital analyses used mks units while the other group that was developing the flight software was using English units, and over the entire multi-year program no one ever noticed that they were inputting data in mks units into a flight computer programmed for English units. Well, I can't resist one more, the Hubble telescope and its astigmatism requiring a corrective set of eyeglasses that only partially restored its vision. That screwed up lens sat in a warehouse for several years before launch, and had gone through several inspections, yet it was a big surprise to all when they turned it on for the first time and couldn't see squat.

My point to all this is that while mathematical models aren't perfect the biggest problem is often the people building and using them. I do mine as a hobby, and only in areas where I've never worked before (otherwise it might seem too much like work), but have developed a personal interest and want to better under how things work. On the model I just posted (which is still very much a work in progress) I included multiple user controlled parameters for calibrating it to PSDs with a variety of mods. I'm still adjusting my version of it to try and get better agreement between the model outputs and my measured data.

BTW, have you ever heard of this shop? I'm considering stopping by there in 3 or 4 weeks and getting a complete brake up grade on my early 99. A srw truck must be a rarity in your area, as Rocky kept telling me that he couldn't repack my front wheel bearings!

Rockin S Performance, Ft. Lupton, CO
Performance shop, diesel specialist, BTS installer/dealer
Rocky Horn, 303-907-1465 (*club username BigBully)

 

Yes. He is well known and respected around here. If you visit www.coloradopowerstroke.com, you'll see Rocky, his info, posts, etc. I haven't needed Rocky for any work on my '99, not yet anyway, but the Colorado guys think he's great and everyone around here goes to Rocky when they need some expertise.