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I think the backend will hop regardless, though it does help having less air in them I would think. Up front the engine is so heavy I never run anything less than 80. If it ever hops up front it must be because I drove off a bridge More pressure should always help mpg. Try pushing a truck with flat tires.. The less air in them, the more surface area is touching the road, you want there to be less surface area. I fill my bed with snow (if we had any) too, otherwise I use engine blocks. I didn't know snow added THAT much weight! Though I don't doubt it, mine rode on the overloads last time filled it up, rode so smoooth.

Mine were also 60lbs.. I do run 80psi up front and 70 in back. Rogan surely had the same tires that Mike does on his 12V when he was getting 27. There is just something happening here about the 12 and 24 that I can't figure out. But there are several things that could be adding up. Like my valve springs are not 60lb springs, not sure what they are but they are less. 24V's have 60lb springs and 12 more of them.. Not sure that matters since the energy used to open the valve is sent right back when they close. There is also the deal with compression but the problem is that the HO engines seem to get the same mileage as the SO ones. Supposedly lower compression is needed for higher loads (trailers) and you need more boost to be efficient, which means an SO engine with an HY (your truck John) would be the most efficient with a trailer. But obviously that isn't happening. I am dumbfounded that THracing gets 22 with a 4wd dually 24V at 60-65 with 4.10s, and Rogan gets 27 with a 4wd at 60-65 as well. Yet when I go 60-65, I get 25-23mpg. Th runs smaller tires even (I think) and that would mean it would really be up there in the RPM's with those 4.10's. But if the engine had that much leverage, it would seemingly not have to work at all other than basically free reving to whatever that RPM. On the other hand we have Rogan with big tires doing 60-65 getting 27, that tells me low engine RPM and an advantage at miles per tire revolution can also gain you. What I mean by that is if I go 1500RPM, the engine isnt working but I'm not getting anywhere either, maybe 50mph. If Rogan went the same RPM, he might be at 60mph, so he racks up more miles which are part of the mpg equation. So it seems you can beat the odds in a couple different ways. Giving the engine so much leverage that it doesn't even have to work, or allowing the engine to rack up miles at low RPM using slightly larger tires (I don't think Rogan was using overly aggressive tires or anything, just bigger diameter than me). That is why I want the 3.07, it would give me both advantages. 3.07 would rack up miles at low rpm, but the small tires would give me the leverage. I believe getting the miles up through the axle ratios is more efficient than trying to get them up through tire sizes, since bigger tires also come with added weight you have to push. --- Update to the previous post... Alright I was reading some conflicting info on the compression ratio crap. Finally found efficiency formulas that prove what a more efficient engine needs. It says you want the charge air to be as low of temp as possible and the temperature after combustion to be as high as possible. To accomplish this you need as high a compression ratio as you can run safely. So high EGT's are actually what you want..as long as they do not exceed the limits of the pistons. It seems you can run 1100F or so all day long on these engines so that would be optimal, but getting there with as cold of intake air as possible is a big challenge. I will try and get a calculator going and see what I can figure out.

2011 looks interesting on my computer. I was asleep by 11 so it worked out. Just watched the ball drop on youtube, interestingly enough, everything is exactly the same as last year, down to the couples making out, the times square hats, I watched the 2010 one last night and thought I was watching it again until I read 2011 on their hats.

Went and weighed it with me in it and a full tank of fuel. Exactly 6600lbs. Guessing it would weigh ~6300 stock without me in it. As in, only 2 batteries, no tool box, no tools in my cab..

It's my job I don't have any problem writing long posts. I rarely get to do it.

Sounds just like this

Hope you all have a good New Years. Don't get too drunk or anything :moon:I accomplished a whole lot of nothing this year. To pay tribute I will be asleep when it rolls over, like I was last year Anyone doing anything interesting tonight? Starring at a TV watching a ball drop doesn't count

Yeah I just saw DieselD24's post and instantly took off writing. Then I scrolled up and saw Stodg had everything explained already But it made me feel good inside

I think there is a misconception about kerosene. It is not as dry as sand. The machine shop I worked in used kerosene when machining things and it worked great. True it doesn't have the lube of regular #2, but it still has lube in it. I have no idea how worthy 911 is. Regular power service anti gel is uh, an antigel..so what is 911? Only thing I can think of is it must be extreme and have extreme anti-lube properties. According to this page, regular PS is crap, only improving HFRR a little. Which means the antigel PS must really suck, so now where does that put 911.. Even here on post #41, he says "I have seen a LS#2 mixed with ULS#1 and the HFRR result improved (on multiple tests)." Which is LS#2-Low Sulphur #2, and ULS#1-Ultra Low Sulphur #1 (kerosene). Here it says in post #14 "Jet A is just kerosene and I get drums for free. Jet A has a HFRR wear scar of 670. ULSD untreated has a HFRR wear scar of 640." Further showing it isn't dry sand, it is just 30 points behind the regular #2. I would use mixes of kerosene (#1 diesel) first.

That's exactly what I was thinking. Didn't want to point it out though But yeah there is nothing there and seems to me it was just one guy judging everything by their cover.

I don't know what to believe with compression ratios since everyone is posting different numbers all over the place. I am just gonna have to measure it some day. The OE service manual also says max fuel pressure of 25psi for my truck which is a load of crap.

It has been down to -2F and the fuel didn't gel or anything, I don't add any additives. I have gone from here to detroit at 70, got 21mpg. Here to Denver at 70, got 21mpg. Here to Nebraska at 70, got 21mpg. I seem to get 21mpg at 70 Cruise was set going to detroit.

What's funny is in the summer when I got the same mileage, that was with amsoil.. Now it's winter and running conventional premium blue I get the same numbers. I got my winter results at the same freezing temps so that throws that out. Frontal area might be something but I have a big brush guard and towing mirrors to add to it. I will have to run into town at night where they leave the scales on at this one place and see what I get. Tires are the stock 245/75's. Now throw into the equation that Thracing gets 22 at 60-65 with his 4.10 Dually In canada's cold and his is a 24V. I need to get Guesswho to test everything since his truck as identical to mine in every way and we see about the same temps and terrain. As for timing. I made this. Basically I enter a baseline which if stock is 13.5 and we have a range of about 700-3000RPM, then you can average that out to 1850, use the time it has to go from 13.5-TDC as a baseline time, and figure out what timing would have to be at at all other RPM's to equal the same time. Pretty interesting. On the left it shows all the specs of 1850RPM at 13.5* Timing and the "Injection to TDC Time" is what the very right column matches. The 2 columns to the left of the very right are actual times if the engine was at the baseline timing the whole time (like 12V's are).

Lifted trucks are bad for mileage, especially with big tires. 4.10 would seem to help you a bit in this instance though. But you are still pushing big tires and having to push a lifted truck through the wind, the lower the truck the better. A cracked exhaust manifold would allow pressure to escape and in turn reduce the drive pressure that the turbo sees which means less boost. It would be inefficient. Do you have a chip on it that advances timing? That supposedly helps a lot. Same with an aftermarket lift pump. The VP44 advances timing hydraulically with fuel pressure. If your fuel pressure is low, you hardly have any hydraulic force to advance the timing, so it doesn't happen. This is why everyone sees a 3mpg or so increase when they go from a deadbeat stock pump, to an airdog or the like. Then there is the cold weather that drops it down as Mike has proven in the mpg thread.

It had more power without the front too, didn't it. It hit 67F here (pretty sure we broke a record) and I had to step on it and it was back to being a little slower. When it gets under 20F I can just fly, spools like crazy and everything. Time to add another toggle to the high idle box