What mpgs with 7x0.010?

[Southpole560]

What type of mpgs can I see with 7x0.010 if I have a light foot? I just ordered a set from DAP and am going to replace my 50hp injectors that I got years ago from diesel speed shop. The best fuel economy I have gotten with them lately is 18-19 hand calculated at the pump. I'm very very light on the throttle and usually the slowest on the road cruising at 60. I could have sworn that when I first got those that I hand calc'd near 20-21 but can't seem to get those figures anymore. Also had the pressures set to 310 bar at a local shop and they told me that 2 were starting to leak but that it shouldn't affect fuel economy and might only be a bit smokey on startup (which is what I was experiencing before). This is why I have chose the 7x0.010 injectors and to also have a little fun sometimes. I have a quadzilla adrenaline with v2 tuning and am planing to dial in those injectors really well for fuel economy. I'm going to start with mopar1973mans tune and adjust from there. Also, is there any timing difference between the stock 235 hp engine and the HO with the 17.2cr? I'm wondering if should adjust my timing a little lower or possibly higher to compensate. I also have the HO vp44 but I may go to a SO in the future to see if there will be any differences in fuel economy with the HO motor. Thanks guys!

Edited February 22, 2020 by Southpole560
Typo

[Me78569]

With your tires 18-19 is pretty good.  I wouldnt expect too much more.

[Southpole560]

Hopefully it stays the same if it doesn't go up. I'm due here for new tires and I'm going to go with 33s instead of 35s. If I could, I would go with the stock rims and stock tires but unfortunately I don't have space for them at the moment. When I bought my truck, it came with 17x10 rims (maybe 17x9 but I can't remember) so I believe the smallest tire I can put on it is a 285/70-r17

[dripley]

What gear ratio are you running?

[Southpole560]

3.54 ~1600 rpm @ 60mph.

[dripley]

I am getting 18 to 19 running 70 to 75 with 354's on 265 75 16's. What you are getting on those big tires is pretty darn good compared most we see with similar set ups. 

[Southpole560]

That's only if I have a really light foot and baby it though. I've seen it as low as mid 16s-17s if I give it a bit more throttle and try to keep up with traffic at lights or on the freeway. Last trip I had cruise set at 65 and went from Portland to the Wildhorse casino in Pendleton. Got 18.9 mpg that run but I slowed down a little and let the momentum bring the truck up the small grades down to 55 mph then slowly back up to 65. I have also taken off my cold air intake, put the BHAF back on, taped up the fender intake duct, and threw my winter front on to get warmer air to the engine. Supposedly the warmer air should net me better mpgs but would also have a slight power loss. Once I have the available space, I'm getting the stock tires and rims lol.

[Dieselfuture]

If you keep driving habits same you should be in same mpg especially with quad. If you can have them pop injectors at 320-324 or so, it will help everything. 

[Southpole560]

I just ordered the injectors the other day and asked if they were able to set them to 320. Hopefully they can. I ordered the 7x.010 VCO aftermarket body injectors. Looks like they had them on sale. If for some reason my mpg goes down, I'm gonna flip haha 

[Threadzy]

I ordered their 7x10 SACS and some head studs. Getting them set at 325 bar. Looking forward to dialing in a new tune. 

[Southpole560]

I originally was going to order the sac injectors but ended up going with VCO's for max fuel mileage. Everything I've researched has seemed to have said that VCO's will get slightly better mileage over sac's. My buddies tell me that I'm a hypermiling bas**** 

[98whitelightnin]

Mpg shouldn’t go down and you should be able to fit a 265/70/17

[Mopar1973Man]

19 to 21 MPG is my best so far.

Edited February 23, 2020 by Mopar1973Man

[Southpole560]

1 hour ago, 98whitelightnin said:

Mpg shouldn’t go down and you should be able to fit a 265/70/17

 

Would that fit on a 17x10 rim? When I looked it up on a tire size comparison website, it said the max would be a 17x9. If I could possibly fit those tires on my rim I might just see an increase in my average fuel economy hopefully.

1 hour ago, Mopar1973Man said:

19 to 21 MOG is my b est so far.

If I can get to 20, I'd be more than happy. I also forget to mention that I have a ton of stuff in my truck and a tool box in the back filled with tools. When I drove over multiple scales they showed that I was at ~9000lbs. I'm sure my tank average is hit by that slightly but I have to leave all that stuff in my truck for the time being. Maybe that could explain the slight drop in average mpg over a course of about 5 years.

 

By the way, how did you manage to get your all time high to 27mpg? Was it mainly hypermiling the truck for that tank? 

[Mopar1973Man]

7 minutes ago, Southpole560 said:

If I can get to 20, I'd be more than happy.

 

Need to get your final ratio to the ground between 3.55 and 3.73. So for example my truck came with 265's and 3.55 gears. Now switching to 245/75 R16 that drop 1 inch on tires and final ratio to the ground is 3.69:1. This makes for optimal high speed travel. I've done plenty of 2,500 RPM runs at 80 to 85 MPH and netted 20 to 21 MPG. 

 

On the scales I'm barely 7,300 to 7,500 pounds on average. Need to shed lots of weight. That like towing my empty trailer behind your truck. My BigTex 70TV is exactly 1,800 pounds empty. I learn long ago not to carry any tools in the bed or truck. Does absolutely nothing. 5th gear disappeared. Nothing a toolbox could do, no way to fix. Lift pump failed, nothing a toolbox can fix without parts. Broke the mainshaft in the transmission nothing a toolbox will fix. I stopped carrying tools. 409k miles later and toolbox could fix ZERO of any failures I've had!

11 minutes ago, Southpole560 said:

By the way, how did you manage to get your all time high to 27mpg?

Edge Comp, RV275 injectors, road speed limited to 55 MPH and MPG fooler was being used to retard timing. (Not advance). Now knowing these tricks from the past I've been able to keep 500 HP and still keep 19 to 21 MPG most of the time. Matter of fact Edge Comp broke the mainshaft in my transmission. My angle is remove as much drag and rotational mas and the power natural comes out. Currently 3rd, 4th and 5th gear are known to spin the tires. 

[dripley]

How are figuring your miles driven? Is your odo adjusted for the tires? You are gerring 30% better milage than anyone I have seen on here with 35" tires + 9000 lb gross weight. 

[Southpole560]

23 minutes ago, dripley said:

How are figuring your miles driven? Is your odo adjusted for the tires? You are gerring 30% better milage than anyone I have seen on here with 35" tires + 9000 lb gross weight. 

GPS and yes it is corrected to the tire size. I've actually recalibrated it again since my 35's are worn down. I'm actually getting 30% better? I guess my hypermiling is somewhat paying off then lol.

[dripley]

1 hour ago, Southpole560 said:

GPS and yes it is corrected to the tire size. I've actually recalibrated it again since my 35's are worn down. I'm actually getting 30% better? I guess my hypermiling is somewhat paying off then lol.

Me for comparison, 265 75 16's, 355 gears, 7300 gross am 18.5 mpg at 75. I was getting 19.5 prior to replacing my VP last Thanksgiving. Pump is not tapped ma be the reason for the loss not sure.  But if I added 1700 lbs i would expect it to drop a couple mpg I would think.

 

I could slow down 65 and that would help but extra time to the trips home I make. 

Edited February 23, 2020 by dripley

[Southpole560]

17 minutes ago, dripley said:

Me for comparison, 265 75 16's, 355 gears, 7300 gross am 18.5 mpg at 75. I was getting 19.5 prior to replacing my VP last Thanksgiving. Pump is not tapped ma be the reason for the loss not sure.  But if I added 1700 lbs i would expect it to drop a couple mpg I would think.

 

I could slow down 65 and that would help but extra time to the trips home I make. 

That's pretty dang good. What tuning file/timing are you using?

19 minutes ago, dripley said:

Me for comparison, 265 75 16's, 355 gears, 7300 gross am 18.5 mpg at 75. I was getting 19.5 prior to replacing my VP last Thanksgiving. Pump is not tapped ma be the reason for the loss not sure.  But if I added 1700 lbs i would expect it to drop a couple mpg I would think.

 

I could slow down 65 and that would help but extra time to the trips home I make. 

That's pretty dang good. What tuning file/timing are you using?

[dripley]

2 minutes ago, Southpole560 said:

That's pretty dang good. What tuning file/timing are you using?

I have an Edge Comp on mine. No adjustability. Just whats in the box. It is a 5 level tuner 60 to 120 hp. It has 5 sub for brining on full fuel based on boost. Thats it. Right now level 4 and 5 are not available since the pump is not tapped. Vouds my pump warranty. A quad may be in the future.