16 MPG ..... Please Help !!

[theholycow]

Jay, what engine is in your 3500? I just find it hard to believe that they would invest in a whole new control system for the same engine and transmission that is used in other vehicles.

[Jay2TheRescue]

5.7 liter V-8. I know it doesn't make sense, but it is what it is. I tried to use the scangauge on it once, and the computer connector is different. Same with my dad's RV (2008 E450 Super Duty)

[theholycow]

Interesting. I wonder why they do that? Merely not being required says why they don't have to do it but it doesn't say why they'd go to the extra expense of using a new system instead.

[Jay2TheRescue]

My only thought is maybe they have to pay a licensing fee to use OBDII, so its cheaper to use their own proprietary system? I also imagine that the system is not scratch made, but an evolution of the system they were already using prior to the OBDII requirement on light duty vehicles.

[PhileasFogg]

Okay ..... What is OBDII?

[theholycow]

OBDII is the standard/protocol for the diagnostic system that allows universal diagnostic and live data devices like the Scangauge and Ultragauge to work. It is an interface to the main engine control and emissions systems (among others).

[Everett]

Originally Posted by PhileasFogg

holycow .... what about tuners like the Bully Dog? Do they work?

Yes they work. They re-tune the fuel maps for better economy or more horses. I have the Sct model for my mustang and a hypertech for my chevy. You aren't gonna get much better fuel economy than you are already getting. Stay under 60 mph and keep your foot out if it. 2 stroke oil seems to negate the I'll effects of ethanol in my chev 5.3

[benfrogg]

HC-
What ratio of 2 cycle to gas are you using?
I've got a gallon of 2 cycle oil that isn't being used....
B

[theholycow]

Originally Posted by PhileasFogg

holycow .... what about tuners like the Bully Dog? Do they work?

Oops, I missed this post before. I agree with Everett.

Just consider the constraints and priorities the manufacturer had when they programmed it vs. those of the tuner...who's more interested in reliability vs. emissions vs. economy vs. power vs. whatever else. It's not like the manufacturer's engineers are going to just conveniently forget to get those extra 20HP from the engine.

Also remember that 99.9% of the market for products like that is not people driving for fuel economy, but rather people who drive hard and fast. The products are designed to make more power, and sometimes to provide less-terrible fuel economy for people who drive like that. Of course their sales literature (and their customers who need to feel good about the money they spent) all guarantee a major increase in fuel economy but credible, accurate data is sorely missing.

Better than a handheld preprogrammed downloader is a custom tune, which, for GM V8 engines, are widely available from expert custom tuners at costs similar to a downloader. Blackbear Performance is one company I'm aware of that does it. If any tune can help, a custom tune (after you tell them how you drive and how important fuel economy is to you) is it. It may take a lot of miles to pay for itself though!

[theholycow]

Originally Posted by benfrogg

HC-
What ratio of 2 cycle to gas are you using?
I've got a gallon of 2 cycle oil that isn't being used....
B

I don't use it, except in 2 cycle engines (at the specified ratio).