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First mileage test result.

Camper_Jeff___K
Nomad III
Nomad III

The first mileage test results are in.

A quick review of what was done to the truck.

Cometic head gaskets half the thickness of Fel-Pro and with full o-rings around each cylinder, not combining into one ring between cylinders like Fel-Pro. This raised all compressions from 185 to 200, to 200 to 220. ARP head studs at true 90 pounds torque instead of garbage unreliable twist to yield factory head bolts. New Melling timing chains, tensioners, chain guides and Melling 176 HV high volume oil pump with lower pressure spring installed. Porting out the exhaust ports to gasket match the new headers. A pair of Gibson 1-1/2" ss tube headers. SPD Performance Y-Pipe modification to exhaust creating better flow and scavaging. The MMR Racing coolant adaptors to the backs of the heads and plumbing them into the coolant return tube to the water pump for better cooling. Fabricating a larger 3-1/2" cold air inlet. Removing the comb like teeth in the throttlebody intake gasket improving intake air flow again. Welding shut the unused rear of head intake manifold coolant passages to prevent leaking due to the cheap plastic stock intake manifold. Modifying the intake manifold crossover tube connections to improve sealing and reduce the chance of the common leakage problem from happening again. Using the crossover clamp device I thought up to further increase the likelihood of a permanent seal. The injectors are 1 year old and all NGK ignition coils are 8 months. Several sensors were also replaced, MAF, O2 L & O2 R, TPS. All sensors about 6 months ago. 

Ok, so what are the mileage test results?

After 140 miles of mixed city, arterial, freeway driving, the resulting MPG is 11.75

11.75 MPG may or may not impress people but, it is a 2000 F-250 super cab 4x4 with a 5.4 liter 2 valve engine and 4 speed automatic. Before, we were getting 8 or 9 mpg, "10 on a really good day without the TC on". 

This represents an improvement of 3 to even 4 mpg. That will add up to decent savings over time. I just need to stay on top of maintenance to keep it this way. Regular oil changes at 3000 miles or less are very important, especially if you drive a truck with the 3 valve engine.

Everything I did to the engine, is on video and was posted to this forum if you're interested.

Thats the end of the truck repair/improvement video series. I hope those who saw it, enjoyed it. And now you know the fruition, end result.

It's back to camping soon.

 

 

 

36 REPLIES 36

Camper_Jeff___K
Nomad III
Nomad III

An update on the truck's mileage per gallon. I drove from Seattle to Spokane and back over the weekend. Our speed was 75 to 77 for the most part.  We drove over Snoqualmie Pass. The truck with the new engine setup, held speed in cruise control without dropping in speed only downshifted to third. With the old engine setup, stock form, it would not hold speed in cruise over the pass and would drop to 60 mph or less sometimes downshifting into second, skipping third. I'm quite happy with the performance. We did hit 12 mpg on the button at those speeds. I expect it will drop some when the TC is loaded next week. Now I need to remove my rear seats and build platforms in back to stack supplies and tools in the back seat area. We also need to fit in 2 cat carriers and a litterbox for cat comfort. That's the latest development with the truck project. 

Sounds like success to me!  We travel with a pup and our cat too, we keep a litter box on the rear seat floor. 

2014 Wolf Creek 850SB
2012 GMC Sierra SLT 2500HD 7,220# Truck/10,400# Camper Fully Loaded

We enjoy having the little darlings along and they pick up their travel routine quickly. When the voyage is over, they have to readjust to the cavernous house. They're both great travelers. Unlike Good Old Charlie, these two knuckleheads can't become leash certified, so they only go outside in an enclosed pen, supervised because so many people feel their dog is special and can freely roam the campground.  Currently removing rear seats and designing a platform system to improve storage situation. Platform will accommodate a large litter box and two carriers plus food, tools and things bottom level.

opnspaces
Navigator II
Navigator II

Hey StirCrazy, are your LS swaps keeping the factory fuel injection or are they all converted to carbureted?  I swapped a 5.0 mustang engine including the factory fuel injection into my old Bronco in the late 90's. It's the best thing I ever did for that Bronco and I'm still happy every time I hit the key 20 years later.

.
2001 Suburban 4x4. 6.0L, 4.10 3/4 ton **** 2005 Jayco Jay Flight 27BH **** 1986 Coleman Columbia Popup

when we do them we keep them fuel injected..  My buddy went to the US and did a 6 month course on tuning when he retired from the military.  realy it just doesnt make sence to go carberated, unless your building a 4000hp drag car I guess haha

2014 F350 6.7 Platinum
2016 Cougar 330RBK
1991 Slumberqueen WS100

Oregun
Nomad
Nomad

Surprised your mpg's are that low.  I have a 2WD 99 F350 supercab with V10. Drove it to Medford and got 13mpg's unloaded.  I drive the speed limit.  Was surprised I got that good because it only gets 10 around town.  Maybe it's the 4x4 that hurts your mpg's. (just a thought)

 the 5.4 is whats hurting him.. the 5.4 (stock) has to work real hard to move that sail down the road.  the 4x4 doesnt actualy use that much gase when disconected in thoes trucks, not like back in the 60's and 70's  in comparison your V10 is hardly working at the speed limit compared to what the 5.4 would me, and like mu old 99 7.3 diesel it got close to 18mpg with my camper if I drove nice but it was far from stock..  my new 6.7 gets 19's with the camper on.  and it is a 4x4 crewcab long box beast haha

2014 F350 6.7 Platinum
2016 Cougar 330RBK
1991 Slumberqueen WS100

I'm hoping we will get more than 13 mpg with only freeway driving. My truck is 4x4 so there is a little more rotating mass.

I noticed you did't change the cams, was there a reason for that? just wondering as that could have made the difference between the gas milage you got an a point or two left on the table.  also is the muffler stock or have you put a free flowing one on it?  

2014 F350 6.7 Platinum
2016 Cougar 330RBK
1991 Slumberqueen WS100

I didn't want to change the cams as they looked and worked fine. The engine only has about 25k to 30k on it since the rebuild. New cams would be in the 800.00 plus range plus new followers and lifters. It adds up fast.  The engine has new cam followers, valves, pistons. I did swap the new Melling 176 oil pump with a new Melling 176HV pump. I put my efforts into getting as much power and torque out of the engine as built, by improving the breathing ability. I have attempted to achieve better breathing in several ways and I can feel a definite improvement in engine performance. To remind you and other readers of what I did to the engine, here is the list. Cometic MLX Head Gaskets which increased compression pressures from 185 to 200, up to 200 to 220 PSI in the cylinders. The increased compression due to the thinner Cometic head gaskets will make some difference. I installed the heads using ARP head studs at 90 pounds torque. Much more reliable than guessing with stock twist to yield bolts. For improved cooling, I installed the MMR coolant adaptors on the backs of the heads to improve head cooling and to provide a second path back to the water pump to insure no cooling issues will ever happen again. Don't forget the larger core aluminum radiator too. I Ported the exhaust ports and port matched them to the Gibson SS short headers. I removed the stock exhaust, getting rid of that ridiculous 180 degree U-Turn and eliminated the joining of the left and right side exhaust where the two pipes connect and flow straight into each other. It's as if the engineers designed the exhaust for maximum restriction! I replaced the stock exhaust with a Y-PIPE performance kit that straightened out the pipes and directed the flow into a large Y collector that goes into the stock 3" pipe to the catalytic converter and then to a NAPA SS stock replacement muffler with 3" in and out pipes. I fabricated a larger cold air intake and removed the restrictive comb teeth in the throttle body gasket which by my estimation, opened the air flow by a good 10%.  It's a good engine (though under powered), except for when the water pump which failed and over heated the engine, ruining the Fel-Pro head gaskets which over the course of our road trip, got progressively worse, losing coolant, then also oil, then also compression blowing into the water jacket. 

All in all, I spent close to 6000.00 doing the work I did. That amount is materials only, I did all the work myself to keep costs down. Cams with all the stuff that goes with them would have added another 1500 to 2000 to the cost all said and done. On modern engines, it is likely I would have had to have some retuning done to the engine, for the new cams to be optimized. Another option I have with the stock cams is to buy a tuner and load a torque, tow / haul program into the truck computer. Switch back and forth from stock setting, to tow/haul setting,  as needed for travel. 500.00 for a tuner.

I think I've covered everything. We hope to hit the road in a week or so to give the truck and camper a good shakedown cruise before Snowbirding South. I've installed the best parts for their purpose I could find, and hopefully it will pay off. I've made my best attempt to "Bullet Proof" if you will,  this engine! 

I drove pretty much all 4.6 and 5.4 Fords, new trucks, for the entire run of that engine platform. I’d run them 30-40k mi per year and get a new one every year or 2. Buncha 1/2 tons 2wd and 4wd and a few 3/4 tons 2wd and 4wd. 
13mpg was a good round number for a 1/2 ton 2 wheeler. Don’t think I ever saw that in a 4x4 except doing downhill. V10s about the same. Had a couple of those too. 10-12mpg not towing mostly highway. 
The Coyote and 6.2 were a small improvement in mpg and a big improvement in power, partly due to the 6speed. 

2016 Ram 2500, MotorOps.ca EFIlive tuned, 5” turbo back, 6" lift on 37s
2017 Heartland Torque T29 - Sold.
Couple of Arctic Fox TCs - Sold

StirCrazy
Navigator
Navigator

did you ever think about just putting a different engine into it?  I'm not asking this to stir anythign up, but the 5.4 wasn't that great of a engine to start with and with so many new offerings from both ford and gm that would be easy to swap in and would give you more power and better fuel economy.  for example a junkyard LS 6L could be had with a trans for about 1500 up here so 1000ish down their and prople about another 500 in parts to install it, I bet you would be well over 15 mph.  I know its a gm motor in a ford, I am just using it as an example and it is the cheepest way to go, the ford gas engines that would make a good swap are a little more money.

2014 F350 6.7 Platinum
2016 Cougar 330RBK
1991 Slumberqueen WS100

Ain’t no old LS getting 15mpg in a 3/4ton 4x4.   
plus F250 LS swap?  Rofl. Can’t see anywhere that might get difficult or have issues…..

2016 Ram 2500, MotorOps.ca EFIlive tuned, 5” turbo back, 6" lift on 37s
2017 Heartland Torque T29 - Sold.
Couple of Arctic Fox TCs - Sold

no it would probably get better.  🤣

LS into anything is easy now days, they make mount kits for almost any aplication you can think of, and their cheep including the harness or you can buy an aftermarket harnes and its all plug and play for the most part.  that was just an example, like I said, a coyote swap would be fun also but I think its more suited for hot rods and not things that need low end, and its much much more expensive.  I even have a friend who put a cummins into a old ford 1 ton 4x4 , we had him comitted for using that POS engine but he did it 😆

seriously thought, myself and my two buddys have now swapped about 15 LS motors into classic trucks some as old as the 40's but a lot of 1960's and 70's stuff also.  a few of them are street/strip procharged, one a turbo setup but the rest are all naturaly asperated and if you keep the foot out of them they get amazing milage.  its all about building them proper for what they are going to do.   

2014 F350 6.7 Platinum
2016 Cougar 330RBK
1991 Slumberqueen WS100