Dodge Cummins Diesel Forum banner
  • Hey everyone! Enter your ride HERE to be a part of October's Cummins of the Month Challenge!
1 - 17 of 17 Posts

·
Registered
Joined
·
519 Posts
Discussion Starter · #1 ·
Hey, guys,

I'd like to revisit the question of "which mods help most?" when referring to fuel mileage improvements, especially since we've seen a lot of new product introduction in recent weeks.

I'm constantly tweaking my Edge/MP-8 settings to milk every mile from every gallon, just like the rest of you.

Next week I'm going to add a "Smarty," injectors, and a Stage III CP3 to the equation, both for the performance, "seat of the pants" gains, but also with the hope that my fuel efficiency will be helped (provided I keep "my foot out of it.")

With the introduction of the XRT tunes, the Smarty, a couple of new "boost foolers," and other tuner/software updates -- not to mention a number of forumites adding "twins" to their trucks -- I am thinking it might be helpful to look at which mods (or combinations of mods) have netted the biggest gains in MPGs.

Any input would be appreciated, but I'm interested (for obvious reasons) in hearing from guys who've done injector mods, pump mods, or realized gains from the new Smarty.

Thanks!
 

·
Registered
Joined
·
1,407 Posts
I'll be interested to see the mileage return on dollars invested.
 

·
Registered
Joined
·
519 Posts
Discussion Starter · #3 ·
I'll be interested to see the mileage return on dollars invested.
Valid point.

It takes a long time to recoup the $ spent on mods, especially now, with fuel back down under $2 in many parts of the country.

For me, it wouldn't make sense, if mileage improvements were the only benefit to modding my truck. Fortunately, it's a lot more fun to drive, now, and the oil stays much cleaner (not to mention intake, turbo, etc.) so there may be very real longevity gains, in addition to the benefit of less trips to the dealership, when the warranty goes out. My regular warranty expires in a couple of months.

I'm making a couple of assumptions: 1) Fuel will likely go up in price, before it drops any lower. 2) I will keep this truck for at least ten years, as I did my '97 CTD 3) The newer generation emissions controls will become increasingly difficult to "mod," and will have an increasingly negative effect on fuel/mileage performance.
 

·
Premium Member
Joined
·
713 Posts
I run the Smarty and an intercooler with big boost tubes and I get 22.5 miles per gallon. ( HWY )

I need to put in my new clutch, Shibby intake horn and Air Dog still

and 24 miles per gallon running 60.

I'm going to do more adjustments after the clutch is in. :thumbsup:
 

·
Registered
Joined
·
519 Posts
Discussion Starter · #6 ·
flex a lite fans seem to do well.. Flex-a-lite 264 - Flex-a-lite Monster Direct Fit Electric Fans

getting rid of that front bumpergaurd would help, reducing weight and air drag. (but let's not go crazy)lol
You are right about the winch/bumper, but this is elk country, and front-end protection is a necessary evil. Hit a 1600 pound bull elk, and your fuel mileage suddenly becomes really, really bad. :hehe:

Do you have the Flex-a-lite fan?
 

·
Registered
Joined
·
519 Posts
Discussion Starter · #7 ·
I run the Smarty and an intercooler with big boost tubes and I get 22.5 miles per gallon. ( HWY )

I need to put in my new clutch, Shibby intake horn and Air Dog still

and 24 miles per gallon running 60.

I'm going to do more adjustments after the clutch is in. :thumbsup:
How do you like the Smarty, and what are your settings on it? Also, how much of a MPG improvement did the Smarty make? I am running the AFE tube from the intercooler to the stock intake horn, but I didn't notice any HP or mpg improvement after installing it.

My current mods have added about a 3 mpg increase (so far on winter fuel), but I'm hoping the new 80hp injectors and modded pump make a difference, too.

Your mileage is much better than mine. I'm seeing 16-17 on state road driving and 18-19, tops, on the interstates going 65-70.
 

·
Premium Member
Joined
·
713 Posts
How do you like the Smarty, and what are your settings on it? Also, how much of a MPG improvement did the Smarty make? I am running the AFE tube from the intercooler to the stock intake horn, but I didn't notice any HP or mpg improvement after installing it.

My current mods have added about a 3 mpg increase (so far on winter fuel), but I'm hoping the new 80hp injectors and modded pump make a difference, too.

Your mileage is much better than mine. I'm seeing 16-17 on state road driving and 18-19, tops, on the interstates going 65-70.
Smarty gave me 2 more, I just have set at SW7 130 hp w/ timming.

Want to put in the SBC clutch before I mess with anymore settings.

I love the Smarty. Thanks Bob Wanger for the Smarty S67 and the 100 Grand!!!!!!!!!!
 

·
Banned
Joined
·
1,844 Posts
i will have to see what i am getting,,with evrything i have ,,i dont think about it cause i dont pay for my fuel its free for me,,one of the lucky ones..
 

·
Registered
Joined
·
456 Posts
You are right about the winch/bumper, but this is elk country, and front-end protection is a necessary evil. Hit a 1600 pound bull elk, and your fuel mileage suddenly becomes really, really bad. :hehe:

Do you have the Flex-a-lite fan?
No, first the deletes. then the fan. Just lost a source of income, so pinching for i bit here. I haven't heard anything bad about them, though.
 

·
Registered
Joined
·
373 Posts
I did my mods for the reliable fun/power factor. Mileage increase is just a real nice added bonus.

My mods are:
Edge Juice W/ Attitude
TS Performance MP-8
EGR delete plates
BADP 4" Gen I DPF deltes (non catted DP)
AEM CAI

These mods were worth every penny. I haven't got to take it on a long highway trip, but my daily driving (65-70% city driving) has yielded a gain of 4+mpg.
 

·
Premium Member
Joined
·
809 Posts
Nothing seemed to work for me. Maybe unplugging the egr helped.
Everything falling off didn't.
 

·
Registered
Joined
·
519 Posts
Discussion Starter · #13 ·
Nothing seemed to work for me. Maybe unplugging the egr helped.
Everything falling off didn't.
I think that's unusual.

My truck started off pretty bad. I was never able to do much better than 12 in town and a one-time high of 16 on the interstate, with my normal about 14.5 or 15.

So, I've seen an increase of 3 mpg, across the board.

I did all my mods in the span of about a month, so it's hard to tell exactly what helped the most. I've plateaued at where I'm at, now, since December, when I the deletes were done and the Edge/MP-8 were added. I think the MP-8 helped the most, but I didn't notice a huge improvement from the deletes, themselves.

I don't seem to be able to break out of the mid-18 range on the interstates, and that's poking along at 65.

I'd like to see 20 on the interstate, and I'd be satisfied; that'd be damned good for a heavy dually, running commercial tires in mountainous terrain.
 

·
Registered
Joined
·
373 Posts
Nothing seemed to work for me. Maybe unplugging the egr helped.
Everything falling off didn't.
Sounds like you are enjoying the added power a little too much and too often.
 

·
Premium Member
Joined
·
809 Posts
Sounds like you are enjoying the added power a little too much and too often.

I have keep very accurate records of mpg's
last 6 months of '07 = 13.75
08 = 14.54
09 = 14.85

Did the deletes, edge, epp approx. 6 weeks ago.

Maybe its gettin better very slowly.
70,000 miles.:confused013:
 

·
Registered
Joined
·
270 Posts
Ive heard bad things

on flex a lite fans. From other pp they say theyre overpriced and they dont last?? I dont know ive never had them... i put some old ls1 fans on my silverado and theyve been doin good for 3 or 4 years and only cost me $100.
 

·
Si vis pacem, para bellum
Joined
·
2,459 Posts
I suppose I have to be the voice of the outlier here. When my truck was 100% stock performance wise, the best I ever got was 17.9mpg on a single tank of fuel running 100% highway. Once i deleted the DPF, NOx, Cat, and EGR I see a fairly consistant 20.5-21mpg all highway. My usual weekly route which is a mixture of highway and city driving with a fair amount of idle time would yield 14mpg fairly consistantly. Once the deletes were performed, the weekly route average went to 17-17.3mpg and rarely went over 17.5mpg. I have tried the Bully Dog Power Pup, the Edge Juice w/Attitude, the DiabloSport Extreme PowerPuck, and the Bully Dog PMT and none of those positively affected my fuel economy either on my weekly route or my highway fuel economy. It would seem my truck just didn't like tuners for fuel economy.

On Monday I installed my Smarty on SW1 with default settings. I filled up today and hand calculated 18.4mpg for my weekly route. This is only 1 tank of fuel so it is far from being an accurate representation of fuel economy thus far but it's a positive start. I have an ~400 mile mostly highway trip to make tomorrow and will log my fuel economy for that as well as see what it comes out to. Again, this will not be enough miles to accurately gauge fuel economy changes but it should start pointing towards any trends.

One other thing to mention is that all these figures are with the truck bobtail. My towing economy varies greatly depending on the trailer I am hooked to (i have 3) and the load I am pulling. I have an ~3000 mile trailer trip to make in the second half of May that I hope to have the Smarty dialed in for maximum fuel economy and will post my results upon my return. Until then, I will update my fuel economy findings with the truck bobtail (and any trailer runs i make between now and then) in this thread. My goal has always been to see a consistant 22mpg out of this truck, bobtail, on the highway. I am hoping the Smarty will take me where so many other tuners have failed to take me in the past. Only time will tell.
 
1 - 17 of 17 Posts
Top