I havent used a tuner yet on a dodge truck, however Ive had many previous cars w/ tunes. From my experience, no tune makes better MPG. Lots of people claim 1-2mpg, but I think it has more to do with conscious driving styles.

I think in SOME cases, it could make 1 mpg difference, but I believe its rare. Do you really think car manufacturers are going to short themselves on the tune and get less MPG than possible, especially with the EPA coming down on them?

Usually though, a tune will amount to a noticeable difference in performance throughout the powerband (usually low-mid range) and give you the ability to change how the car shifts. You wont really lose any MPG from this, but I dont see gaining much if any.

 

Tuners, with an 87 octane tune, will improve mileage some.

The Predator does add fuel but it also removes a lean running condition (on the HEMI that's 13.X air/fuel ratio or higher number) down to a WOT air fuel ratio around 12.5. So, yes, it does richen the mixture but also prevents knock and knock retard, which in my opinion are not good for your engine.

If you are looking at a MPG gain, check out the SuperChips tool. They have an 87 octane tune which will richen the mixture less but may give you the MPG gain you are looking for.

 

If I were to get a tuner, it would be the SC. I'm planning on staying 'stock/mostly stock', so SC would be the preferred choice.

My experience with bikes and tuners is somewhat relative,,, both my bike (VTX) and the Hemi use a Speed Density FI system,,,, In the bike, we just dial in new fuel tables with lower A/F ratio's, Great for power, not so great for mileage!

The Hemi is obviously quite a bit more complex than the bike!!!!

I can see where the most gains in MPG would be acheived by driving habit. I'm pretty durn "slow and EZ" now,,, but a little more low end TQ would be nice,,,

I'm curious how the MDS would respond with an SC 87 tune,,,. (I like MDS, unlike perhaps a lot of folks who purchase tuners)

My 'most common' trip is to work and back,,, About 12 miles one way on 35-45 mph sidestreets,,, flat as a pancake,,, PERFECT 'MDS type' driving,,,

Hmmm,,,,

 

Well, at $287 shipped for the Cortex 3950, I guess I'll try it,,, (New from SC via AMA ZON)

 

Thanks for the lead. It's 290 shipped overnight with a 30 day Amazon Prime trial. I figured I'd just cancel the trial and have the thing tomorrow for 3.99 more.

Awesome man. Truly awesome for posting this.

 

Only (1) more left at that price when I checked earlier this morning,,,

That's a SMOKIN' deal for the Cortex unit!

My Cortex should be in SAT. As it seems most information out there indicates best MPG gains are from the 91 tune, I'm going to 'focus' my informal testing on the 87 / Mileage XS tunes.

Most MPG gains are obtained by your driving habits. Tuner or not, aggressive driving kills your MPG.

I drive pretty conservatively, and try to keep the shift points at or below ~2,000~ rpm in town. (Driving Miss Daisy!!??!!??!!??) I (try to) keep it right at the speed limit on the open highway.

It won't be 100% equal testing, but by limiting as many variables as I can, I hope to prove/disprove and quantify any claims to additional MPG.

 

Cortex 3950

I just checked (4 PM central, 6/4/10) and they are still offering more of these Cortex 3950's for ~287~ shipped.

That's some pretty amazing pricing!

 

There is another good thing about the Diablo . It doesn't leave a fingerprint in the ecm . You may want to check with SC before making that committment .

 

I have to say with the Diablosport in my truck I do not think it helped that much. I am going for the power not the MPGs haha. I think if you were to put it on the 87 tune it would help but I am running the 91oct tune. I also took the MDS off the truck since it had some drone with the exhaust

I think the SC was the better choice for you buddy, good choice. If you are not going to put that much into your truck then the SC is the right way to go.

The footprint I am not sure if the SC leaves one or not. The Predator does allow you to throw the stock tune right back in.

Let us know how it goes man! Also if you have gained any MPGs with it.

 

I sell the bullydog and hypertech at my work and on gas engines i
see more people pissed that they dont see any or minimal gains in mpgs. I used a hypertech econ with a k&n intake on a 98 durango and saw maybe 1 more mpg. Hope this helps.

 

I wonder if the majority of them were 'enjoying' the skinny pedal a bit more than they were before,, or, if they had unrealistic expectations to begin with?

I think a consistent 1 MPG increase would be 'realistic',,, but I'm also prepared to see 'no significant' gains as well,,,

For me, this is more of an experiment than a 'quest',,,

 

Hmmm,,,

From what I understand, the footprints between both units would be roughly the same. There seems to be a yes/no/maybe consensus between users and non-users alike.

Again, no expert here, but I believe once the OEM set up is reinstalled, about the only way they can 'tell' if it was anything but OEM prior would be to compare the current values to any that might be 'stored' from prior cycles. As I understand it, the ECU 'learns' from your habits and somehow adjusts accordingly. This would seem to indicate some data/values are saved,,, What data/values? Couldn't tell ya,,, Is it the data or values 'altered' by the tuner? Again, couldn't tell ya,,,

IMHO, with any tuner, your best 'bet' is to return to stock config and drive a few 'cycles' before heading into the dealer.

Scat, I got to agree with ya,,, The Diablo is more flexible for 'custom' tuning, and if maximum power for your specific set up is the goal, I think the Predator may be the one to help you achieve that. (Moreso than the 'canned' SC programming)

I'm not knocking or praising any tuner just yet. I believe they all serve a purpose.

As I have mentioned, I'm not really shooting for max power... I'm pretty much content with what I have now! The Hemi already pulls my lil RCSB w/3.92's down the road pretty good!

If I get a little more TQ down low without killing my MPG,, Cool!.

The TQ managment reductions in the SC should help it 'lauch' a little bit better,,, Again, I would consider that a pleasent 'side effect', but not something I would use on a regular basis.

If there are absolutely no gains (or losses!) in HP or TQ, but I can consistently squeak another 1-2 mpg HWY out of it, I'll be tickled!

My Cortex should be in either tmrw or early next week. As my type of driving (city/hwy) varies so much, It's probably going to take months before I can formulate an honest and accurate opinion.