Really bad gas mileage
#11
Yeah I agree the hemi wasn't the best option for this truck. He'll with the mileage this low. Why not make it a 6.1 hemi haha. But anyway I know how winter gas gets worse. But I'm talking back in august when I bought it. Ive never hit over maybe 9 to the gallon
And the 26s are in storage for now. I have them listed in craigslist to see what I could get for them
And the 26s are in storage for now. I have them listed in craigslist to see what I could get for them
#12
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Yeah I agree the hemi wasn't the best option for this truck. He'll with the mileage this low. Why not make it a 6.1 hemi haha. But anyway I know how winter gas gets worse. But I'm talking back in august when I bought it. Ive never hit over maybe 9 to the gallon
And the 26s are in storage for now. I have them listed in craigslist to see what I could get for them
And the 26s are in storage for now. I have them listed in craigslist to see what I could get for them
Honestly, the 6.1 wouldn't help. Moving a heavy truck is all about low end torque. The 5.7 is NOT a very good truck engine in it's stock form, especially in a QC 4x4 and even less suited for a Mega. It's got power out the wazoo, but if you look at the chart, it's really all mid-high rpm power.
The 6.1 is even more so, with it's gains well up on the rpm bandwidth.
It's one reason all the guys who jumped on the 6.1 cam in a 5.7 bandwagon a few years back have taken the cam out. It's actually a step backwards on a heavy truck.
Without basically having to introduce a new engine for these trucks, the current 5.7 would best be served having variable cam timing (VCT) which would be a Godsend in these trucks. Ever wonder why a Ford 5.4 with 90 less HP will out-tow a Hemi? Wonder no more, LOL...
#13
#14
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I think going to 91 octane is a bad idea, causes a reduction not an increase I use 89 as per Chrysler Owners Manual which explains a loss of fuel effiency if you go to a higher octane. Further you can drop down if necessary, but don't go higher with Hemi's and MDS in 2007. Then of course you Tuner Guys out there can shed real light on performance. Regards, Michael
Honestly, on a stock or fairly close to stock Hemi, I don't see a reason to run anything other than 89 octane fuel. The thing is tuned at the factory to run on it so 91+ isn't going to do a thing from a performance standpoint.
I don't like to see anyone run 87. Seems every Hemi I've seen or heard tell of blow a cylinder (failed springs not withstanding, cause that was an '03/early '04 flaw) has been a truck that's run 87 on a regular basis.
The "I don't hear any knocking or pinging" doesn't hold any water with me because that is an extreme pre-detonation. You can have continuous pre-detonation and not even know it. This over time is a VERY BAD thing. Honestly, I wish they'd take that "it's ok to run 87, but for optimum performance run 89" BS right out of the manual. Unless you are running a tuner with a tune specifically designed for 87 octane fuel, stay the hell away from it.
Incidently, I did a very thorough test way back in '05 when I got my old Superchips 3815 tuner, I mean right down to keeping a log in a notebook. Best way I could compare directly was to figure out my fuel cost per mile driven. This was conducted with the truck stock on 89 octane, the 87 tune with both 87 & 89 and the performance tune with 93 octane (the "mileage XS" tune was not out at the time) and took into account the cost difference between the different octane fuels.
I found that the lowest cost per mile driven was with the Performance tune and running 93 octane, which makes perfect sense if you were to look at the timing advance on that tune. Even taking into account the extra cost of the premium fuel, it was cheaper. Predictably, the 87 tune/89 octane was second best, followed by the 87/87 combo and last was bone stock with 89. Also, the differences were not dramatic, because of the cost of fuel figured in, if memory serves, the gap from best to worst was like 2.5 cents per mile. Of course IMO if you can even get close to the same economy with the performance tune and 93 octane you should run it and have the performance gains to boot.
The only exception to this rule I've found is an E-Fan. Cost is relatively low (especially for the pick 'n pull fan guys) and especially at low RPMs where the clutch fan is VERY parasitic, an E-fan frees up enough power (makes the engine work less hard) to see an appreciable fuel savings. Of course this is most evident in city driving where it's a lot of stop and go/low rpm travel. The benefit is much less apparent at highway speeds where there is enough power built up to turn the clutch fan without much power loss. Typically an E-fan can free up about 14-18 HP at the crank (8-10 RWHP) and in city driving conditions it's not rare to see a solid 2 mpg gain in fuel economy...
Last edited by HammerZ71; 12-29-2010 at 03:51 PM.
#16
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Actually back then I had my own business, but it wasn't hard to keep track, just writing down mileage in a notebook, how many miles and price paid. Then about every month, changing the tuner and going from there.
As far as my long winded posts lately, I'm working part time due to some family health issues, and don't have any work lined up til after the holidays. That coupled with the damn 25* nights and 45* days with about 35 mph wind is keeping me off the golf course and in the damn house - bored!!!
As far as my long winded posts lately, I'm working part time due to some family health issues, and don't have any work lined up til after the holidays. That coupled with the damn 25* nights and 45* days with about 35 mph wind is keeping me off the golf course and in the damn house - bored!!!
#17
Yea feels good to know im not the only one avg 9-10mpg in the city. Sucks *****. My buddys 07 2500 cummins gets 14. Sometimes I see my mpgs drop to 5.6.
But took my truck out snowboarding this weekend (approx 3.0hr round trip to the hill). Loaded up the truck with 3 buddies. Highways were ****, so stayed locked in 4x4 the whole trip. Varied speeds from 110-80 km/h, up and down mountain roads, passing snow plows, and drivers that cant find the gas pedal. And battling a head wind Avg'd 15mpg. First hwy trip since I bought her at the end of Nov. Not too bad. And thats running mohawk regular (90 oct, 10% ethanol blend).
But as far as a 5.4 triton out pulling a 5.7 hemi?? I dunno man I got doubts I got both trucks parked outside. Both qc 4x4s, tow packages. And I got to say the 5.4 feels underpowered against the hemi. Then again I never pulled any big loads with either of them. Guess a quad trailer dont count. I Should do a pull off and vid it.
But took my truck out snowboarding this weekend (approx 3.0hr round trip to the hill). Loaded up the truck with 3 buddies. Highways were ****, so stayed locked in 4x4 the whole trip. Varied speeds from 110-80 km/h, up and down mountain roads, passing snow plows, and drivers that cant find the gas pedal. And battling a head wind Avg'd 15mpg. First hwy trip since I bought her at the end of Nov. Not too bad. And thats running mohawk regular (90 oct, 10% ethanol blend).
But as far as a 5.4 triton out pulling a 5.7 hemi?? I dunno man I got doubts I got both trucks parked outside. Both qc 4x4s, tow packages. And I got to say the 5.4 feels underpowered against the hemi. Then again I never pulled any big loads with either of them. Guess a quad trailer dont count. I Should do a pull off and vid it.
#19
Dodge dealer poster
Awhile back like say 2003 Dodge dealers had a poster in each dealership explaining the pro/con of FORD DODGE pulling power and engine choice. Now, I paraphase here.......Ford 5.4 are under square and Dodge is over square or vice versa. This explaination by Chrysler engineering meant that Ford had bettler low end torque and Chrysler had a higher power at higher speeds. Meaning the Ford could pull in the take off and the Chrysler could Fly at highway speeds with a lot of power. The over square and under square is a piston stroke to bore ratio. One is narrow and longer one is wider and shorter.
The of course there is no accounting for gears and in my opinion no reason to screw around witih rears over 3.92 lest of course you live on a farm and don't go into town much
The of course there is no accounting for gears and in my opinion no reason to screw around witih rears over 3.92 lest of course you live on a farm and don't go into town much