I have a 2001 3500 dually 4x4 quad cab long bed, stock tire size, nv4500 5 speed with 3:55 gears. What is the average fuel milage expected from these trucks? The only "mods" done that I know of are a FASS ddrp pump in factory location and the exhaust has been replaced but nothing crazy. I measured the tailpipe it's 4" but have not measured the rest under the truck yet. So to my knowledge it's pretty bone stock with 141k on the clock.

 Last I checked I was at about 15mpg. Mainly to and from work, about a 20 Mile drive, about 5 of that is considered city the rest is state route 60mph or highway about 65mph.

 Just curious if I'm around the norm for what I have. Thanks.

Here is a data log of stock duration commands vs the duration commands with my 7 x .009's.  Note that the quad is commanding  less duration than stock offidle.   This is not a tow tune so the upper end is maxing fuel, but that is tune specific.   

 

So lets imagine we have the same truck, cloned, side by side.  One truck has some 7 x .0085's one has 7 x .010's.  They both have the same turbo and thus are limited in airflow.   Peak HP on each truck is 350 hp as a result.   So different injectors same turbo same peak hp.  

 

With bigger injectors you can inject more cc worth of fuel per time duration.   By shortening your duration even you spray your fuel at a more persice time.   Where as if you have smaller injectors you are forced into extending your duration and spraying your fuel across a longer arc of piston travel.  

 

Both trucks are injecting nearly the same CC worth of fuel per injection event, however the 7 x .010 truck is doing that in a shorter time.   

 

That is what keeps egt's in check.  Using the quad you are commanding LESS duration than stock, but you are injecting more fuel per duration.    

 

Here is the Tuning screen for the quad to tune the duration command.  At each PSI you can alter the stock fueling command from %50 of stock, to %150 of stock.   Setting to %100 would be a stock tune.  anything below %100 is pulling fuel compared to stock.

 

 

 

Edited March 11, 20205 yr by Me78569

Thanks for the explanation's 

  I'm new to this computer tuning stuff. Now my head hurts. 

Lol. Yeah what I gather is bigger injectors plus quad could possibly run cooler than smaller injectors 

Seems like alot of work when 150s and 62 turbo are plug and play.

36 minutes ago, Evan said:

Lol. Yeah what I gather is bigger injectors plus quad could possibly run cooler than smaller injectors 

Seems like alot of work when 150s and 62 turbo are plug and play.

 

 

On 3/9/2020 at 10:57 AM, Evan said:

I live and work in ada county though I'm registered in Elmore county.

I think I smke more than you but havent been pulled over.

Getting 15k moving is when I put on a smoke show. Empty I'm just a good haze unless I stand on then  roll some black wich isnt very often 

Plug and play + smoke.   That's not acceptable here.  They have opacity meters and mobile smog units along on ramps.  People can report you and you get a notice in the mail.  

 

Plus every year they do opacity testing on a dyno and do a lug down at WOT in 1:1 gear.  I promise you your truck would not pass here.

Edited March 11, 20205 yr by Me78569

Luckily we don't have that in Ohio yet. 

 So if I understood all that, by running a bigger injector you can deliver the same amount of fuel faster than with a smaller injector which essentially changes the duration of the fueling event. Now, am I correct in thinking that by doing this it affects the egt by burning faster since the fuel is delivered at a more optimum time during the compression stroke?

 Now, say I put 100hp injectors in a stock engine, will there be a 100hp gain with no increase in boost or otherwise? Or, will there at minimum need to be an increase in boost pressure to add the needed oxygen to burn the extra fuel to make the expected horse power?

 If so, is there a way to increase boost without a tuner? Or, would starting down this road with the bigger injectors begin a string of mods that would need done to compliment the previous mods?

2 hours ago, Doubletrouble said:

Now, say I put 100hp injectors in a stock engine, will there be a 100hp gain with no increase in boost or otherwise? Or, will there at minimum need to be an increase in boost pressure to add the needed oxygen to burn the extra fuel to make the expected horse power?

 

The injector horsepower number represents how much horsepower worth of fuel over stock. So 100 hp injectors will flow enough extra fuel to support 100hp over stock, without tuning. You'll still need more air.

 

2 hours ago, Doubletrouble said:

If so, is there a way to increase boost without a tuner?

 

You must, at a minimum, use a boost fooler, or the ECM will defuel.

12 hours ago, Doubletrouble said:

Now, say I put 100hp injectors in a stock engine, will there be a 100hp gain with no increase in boost or otherwise? Or, will there at minimum need to be an increase in boost pressure to add the needed oxygen to burn the extra fuel to make the expected horse power?

 

Instantly you will gain boost with any gains of fuel. Turbo is ran by the expanding gases from the exhaust. More fuel means more boost.

 

12 hours ago, Doubletrouble said:

If so, is there a way to increase boost without a tuner? Or, would starting down this road with the bigger injectors begin a string of mods that would need done to compliment the previous mods?

 

Not clean no. Tuner should be first really then any injector from there can be tuned out and made clean. You can roll back the fuel on the low boost cases and then pour the fuel on once the turbo spools. 

On 3/10/2020 at 10:02 PM, Me78569 said:

you need to drive a truck with a proper tune.  7 x .010's and a stock turbo with proper tuning is nice to drive.

 

@Me78569 ,  Can you describe what the "proper tuning" details should be if I get 7 x 010's?

 

I'm pretty much stock now (except for a fuel boss mech fuel pump, 4" exhaust, southbend stage 2 and BHAF). I'd like to add power mods in the future and not exactly sure what to do but this thread has helped me understand and narrow down my choices. 

 

Caveats:

HO NV5600

Currently running 4.10's, may switch to 3.54's at some point. Factory tire size 235's (and I'll be keeping the 235's for a while since I just got a new set of Michelin's)

Will be doing random towing - at least 10,000 lbs or more (ball or pintle hitch, not gooseneck)

Not looking to spend huge $, just looking for the best bang for the buck that may work best for my current setup / factory turbo & the HO VP44 / 28 injection pump.

 

Appreciate your recommendations. Thanks!

Something at gets timing at or near 20 * at ~60-65 mph.   

 

 

Stock truck no tuner or nothing will  typically net you about 16 to 17 MPG.

 

Quote

2002 3500 2WD Quad cab dually 6 speed 5.9 ho. 230k. Southbend Stage 2 clutch.  Fuel boss mech pump and big line kit. 4" Diamond eye turbo back stainless exhaust w/ glasspack muffler

Being he doesn't have a tuner I can see there isn't any more that can be done for now. I would also have the injectors tested or replaced. If the injectors are older than 100k miles they are done and worn out. Even if it still runs good the pop pressures will be too low and MPG usually suffers from the poor atomization. 

58 minutes ago, Me78569 said:

something at gets timing at or near 20 * at ~60-65 mph

I don't understand what that means. 

 

44 minutes ago, Mopar1973Man said:

Being he doesn't have a tuner I can see there isn't any more that can be done for now. I would also have the injectors tested or replaced. If the injectors are older than 100k miles they are done and worn out.

Thanks. I  understand this. I'm considering the  7 x .010's , I like what  @Me78569  described about them  "more cc worth of fuel per time duration"

 

@Mopar1973Man : What tune or tuner would you recommend if I get the  7 x .010's ?  I'd like to keep the factory turbo for now. 

 

Thanks

Quadzilla adrenaline   

17 minutes ago, Ironforger said:

@Mopar1973Man : What tune or tuner would you recommend if I get the  7 x .010's ?  I'd like to keep the factory turbo for now. 

 

Quadzilla tuner is the for sure bet. You could use some of my tunes. I'm now working on 3 tunes...

• Economy updates
• Performance building
• Towing building

My economy tune currently on my phone is now pushing upwards into the 20's for sure. My current one I dropped the fuel map quite a bit and amped up the timing again. Then the performance tune I'm wider spread of timing. Then pretty steep fuel curve and plenty of wire tap this one is hot running. Now my tow tune is coming into shape a little at a time. I'm hoping to reach a good solid 14 MPG on the trailer. 

Thanks. A member recommend the Quadzilla XZT as well

 

 I'll keep these items on my wishlist for now! 

2 minutes ago, Ironforger said:

A member recommend the Quadzilla XZT as well

 

Skip the XZT you can't adjust the tune to fit the truck. Not as efficient. 

 

1 minute ago, Mopar1973Man said:

 

Skip the XZT you can't adjust the tune to fit the truck. Not as efficient. 

 

Ok good info, 

 

Thanks!

You can get starter tunes here...

https://mopar1973man.com/files/category/22-quadzilla-standard-tunes/

 

If you want you could call me at 208-315-1470 and I'll guide you on tuning a Quadzilla.

@Mopar1973Man Thanks your help is appreciated.

 

I don't have $1000+ to drop on the Quadzilla Adrenaline and the 7X0.010's.   I'll move forward with this once I have the play money to throw at this truck.

 

Yea I know my injectors have high mileage , wish I could do this now. Good to at least know that the quad adren & 7x0.010's are the next step.  At least I know my mechanical fuel boss pump and stage 2 clutch will be able to handle these mods when I'm ready to roll.

 

 

@Mopar1973Man, would those tunes yield the same results on my truck? I don't have a tuner but am asking out of curiosity. Being I have a dually I don't think I will ever get the high mpg's that some do anyway. 

 Also, we've established that my injectors are original with over 140k on them. I've been noticing a slight "hickup" while idling, would this be due to the injectors as well?