Fooling the Computer for Better MPG

[CrawlingCritter]

You would think that as many times over the last 30 years that the oil companies have screwed the auto industry that somebody in Detroit would learn something. IMO a modern truck or suv should get 30 miles+ per gallon NOW:looser: .

 

[ihscoutlover]

While the engines of 30 years ago might have gotten better mileage, realize that the govt emmissions regulations have tightened thanks in part to the good ole state of Calf., which is helping the feds on this emissions crap. The emissions stuff doesn't always work like its designed to, and if you look at the hot rods of the '60's and '70's, those boats probably got way better mileage than the subcompacts of today, cause they didn't have all this smog stuff. Adding the smog stuff restricts the outbound exhaust some, and this is where the engineers and politicians don't get it. Figger that if you ran a straight pipe system you might be okay, unless it needs a certain amount of backpressure, and then it might have to have a muffler. Just my thoughts.

 

[Blaine B.]

Unfortunately, you're going to have to get used to it.

Many genius ideas are accepted because it helps one thing.

But what nobody looks at what it changed and made worse. Most times you end up in as deep of a hole as you did before, and sometimes worse.

 

[mjdavis31]

If you add a resistor the ecm would think the mixture is to rich and lean it out. .02

 

[Harlee&Tahoe]

As I think about it, how much do you trust your O2s any way?
I'd rather go with a wideband O2s, adjustable MAP, find a way to tweak CPS.

 

[MoparManiac]

Well as far as the quote for the Chevy in the Petersons magazine, I have that magazine as well.

They changed the way they measure the mpg since then probably multiple times (I know they just recently did it again).

It takes more into account now I guess? I'm not sure on the specifics but thats the reason you see those two numbers.

As for the old boats? My family has owned mostly old boats ('75 dodge monaco, 68 dodge charger, 70 dodge challenger, 71 dodge coronet).

You know what they all lack that would make them get better mileage? Overdrive.

Sure you can throw some 4.10s in an 8 3/4 with a 440 and haul, but get on the highway and you're done. You'll get about 10-14 mpg all around.

The 87 Ramcharger with 440 that we have? Get's 7. Yep 7 mpg. No Overdrive.

 

[MudDawg]

I have owned over the years various of the old "boats" ...My old Chevelle comes to mind first...'71 model with a LS-6, M22 and 3.91 gears...burning Sunoco or Shell leaded premium....around town 7-8 mpg....on the road 12-13. Or my old LT-1 Camaro with auto and 4.11 gears...9-10 around town and 14-15 on the highway....yes I ran the crap out of them most of the time...the best mileage I ever got from one of my old cars was from a '69 Nova with a 350/350 and M-20 4 speed.....I went on a long trip, and changed the rear axle from the normal 4.10 ratio out with one that had 2.73 gears....on the Interstate it got 22 mpg but taking off was a blue dyed bitch.

My best ever fuel economy was from my first car...a '65 Opel Kadet with a 1100cc motor and 4 speed...it wouldn't run 60 if it fell off a cliff, but it would get 38 mpg on the highway...

 

[1bolt]

You can lead a horse to water... If you guys were at all serious about tuning your 4.0 for leaner mix then you would be all over the tools I mentioned for performance tuning.

Split Second makes the ESC1 for SPECIFICALY TUNING 02 OUTPUT. for less than $200.

So there you have it, your water right there in front of you... now go tune and tell us how you do. And stop debating freakin O2 sensor voltage already:banghead:.

 

[McQue]

You can lead a horse to water... If you guys were at all serious about tuning your 4.0 for leaner mix then you would be all over the tools I mentioned for performance tuning.

A lot of people would like to improve their gas mileage...MILLIONS I would guess...so, if you know it can be done as you suggest, why don't you do it, and then sell the solution to everybody?

 

[Ecomike]

You can lead a horse to water... If you guys were at all serious about tuning your 4.0 for leaner mix then you would be all over the tools I mentioned for performance tuning.

Split Second makes the ESC1 for SPECIFICALY TUNING 02 OUTPUT. for less than $200.

So there you have it, your water right there in front of you... now go tune and tell us how you do. And stop debating freakin O2 sensor voltage already:banghead:.

So lead on with some links, please! HeHaw!

 

[1bolt]

A lot of people would like to improve their gas mileage...MILLIONS I would guess...so, if you know it can be done as you suggest, why don't you do it, and then sell the solution to everybody?

You know that stupid Snickers comercial where the Pilgrim tells the Viking that the Gas station doesn't have Snickers bars? Right before the Viking throws the trash can at the Caddy? You know the look the Viking had on his face? The blinking stupified confused look? Yeah? Okay that's me right now...

Seriously I just told you about a commonly available tuning product already manufactured, and probably patented that allows you to manipulate your 02 signal...

If I tried to claim this "solution" for myself I believe Split Second would sue the crap out of me...

 

[McQue]

No problem...not trying to confuse you...not suggesting you claim their solution...

SImply suggesting that if you believe you can use that product to improve gas mileage, then please tell us how,...many people would pay for a viable solution...

 

[1bolt]

So lead on with some links, please! HeHaw!

Come on :spin1: you all can debate how to modify o2 voltage and which direction to modify it for nearly a year and 6 pages, with links to Bosch and all manner of other stuff but you can't Google Split Second ESC1?

While googling Check out:
Mega Squirt
Apexi
Accell DFI
UniChip
Perfect Power
Holley MPI Commander 950

And a half dozen other solutions that cost from FREE TO BUILD to less than 200 bucks to more than a couple thousand bucks. And range from dyno tuning required to knob adjustable, to home laptop tweakable.

Just because these things are intended for performance doesn't mean they can't lean out your A/F ratio for daily driving... And they can do it in a predictable programable way, that hacking an o2 will never accomplish.

Not only can just about any one of them do what you guys have been debating, a couple of them can also advance your timing, which can improve your mileage even more.

As I said experiment and hopefully report back with your results... If you're wise though you will get both a wide band o2 gauge and a EGT pyrometer gauge. They will tell you two things: How dangerously lean you are, and how efficiently you're burning your fuel.

I'm not saying all this to rip on you guys, I'm interested to see your results, personally I'm too busy trying to make mine go quicker and faster and have no time for squeezing MPG's. Though that might change if gas prices really hit 4 bucks this summer.

 

[FordGuy]

I have seen so many people think they can figure out a better way to increase fuel economy, they never work, they will tell you it helped, but they are kidding themselves. Gas engines are most effect with a fuel ratio of 14:7 to 1, and that is what a electronically controlled vehicle accomplishes. so if your vehicle is operating as designed, why do so many people waste there money? Wishful thinking!

 

[srimes]

I have seen so many people think they can figure out a better way to increase fuel economy, they never work, they will tell you it helped, but they are kidding themselves. Gas engines are most effect with a fuel ratio of 14:7 to 1, and that is what a electronically controlled vehicle accomplishes. so if your vehicle is operating as designed, why do so many people waste there money? Wishful thinking!

No, they arn't. 14.7 isn't magic, and reality often manifest itself diffently than equations would suggest. At 14.7 there will be unburned fuel and 02 in equal amounts due to the limited time for combustion available.

For peak power what do you want? The limiting power factor is air, so you want to be sure to burn all the air. To do this you throw in extra fuel in order to maximize the chance that every 02 molecule can react with fuel.

And for peak fuel effeciency? You want to burn all the fuel. So make sure there's more O2 around to maximize the chance that all the fuel will burn.

 

[FordGuy]

That would be true if a combustion engine could burn 100% of the fuel, but it cant and there is still a optimum fuel ratio which creates the most Torque for fuel used.

 

[gradon]

A couple months ago I was researching the various piggy-back controllers and liked what I read about Split Second. I do plan on buying the PSC-1 sometime this spring.

 

[Ecomike]

No, they arn't. 14.7 isn't magic, and reality often manifest itself diffently than equations would suggest. At 14.7 there will be unburned fuel and 02 in equal amounts due to the limited time for combustion available.

For peak power what do you want? The limiting power factor is air, so you want to be sure to burn all the air. To do this you throw in extra fuel in order to maximize the chance that every 02 molecule can react with fuel.

And for peak fuel effeciency? You want to burn all the fuel. So make sure there's more O2 around to maximize the chance that all the fuel will burn.

"At 14.7 there will be unburned fuel and 02 in equal amounts due to the limited time for combustion available.",

I assume you mean equal masses of unburned fuel and O2? I seriously doubt the accuracy of that statement, especially since their is a huge variation in the molecualr weight of the various fuel molecules, not to mention the huge variations in the molecular weights of the partially burned fuel, like C0, then add in the NOx and its a huge variable that is constantly changing.

I also have never heard of "so you want to be sure to burn all the air" before. Burning fuel yes, but not air.

 

[Ecomike]

Seriously I just told you about a commonly available tuning product already manufactured, and probably patented that allows you to manipulate your 02 signal...

You need to check your facts a little more closely.

The ESC1 only switches to open loop during boost (if you have a turbo, which most if not all of us lack), open loop is a rich power mode, not a fuel saving, fuel efficient mode. When the boost is gone it just copies the same O2 sensor value that the O2 sensor is putting out already, to the ECU/PCM.

This horse followed your lead, Googled, but only found a dry hole.

I did not see any inexpensive, manually setable or adjustable O2 sensor devices for increasing fuel economy via O2 sensor signal tweaking.

I did see some seriously overpriced variable resistors (potentiometers) in a pretty box for MAP and MAF sensor signal tweaking, like the PSC-1 (which did not even turn up in their own search engine which was odd).

 

[Ecomike]

I have seen so many people think they can figure out a better way to increase fuel economy, they never work, they will tell you it helped, but they are kidding themselves. Gas engines are most effect with a fuel ratio of 14:7 to 1, and that is what a electronically controlled vehicle accomplishes. so if your vehicle is operating as designed, why do so many people waste there money? Wishful thinking!

14.7:1 was not selected to optimize fuel efficiency, it was selected by EPA to minimize air pollution and waste just enough fuel to supply the needs of the catalytic converters. The cat converters need fuel to burn, in order for them to get hot enough to convert trace, excess CO to CO2, etc......

Also, from what I have read the exhaust valves and timing are set to open early enough to leak just enough O2 and fuel into the exhaust to supply the thermal needs of the Cat converters. That early opening slows and delays the completion of the combustion process.

In 1976 Chrysler made an experimental Lean Burn engine that was the only car/engine in 1976 that was exempt from having a cat converter. It operated at a much leaner A/F ratio. It MEET all the exhaust emissions requirments with out a cat converter, however it had cooling problems due to the lean fuel mixture.

If fuel efficiency tweaking does not work, then why is there such a huge difference in reported fuel economy on here at , specifically I have seen MPGs as low as 6 mpgs (Mine at its worst hit 6 mpg, it is currently up to 15 city/20 mpg highway now after waisting my time tweaking things), and as high as 25 mpgs reported here by others for 4.0 L, XJs!