Computer Programming Reduces Gas Mileage???

[glennc]

Need a little more help here. An aftermarket dealer told me to just add CAI and cat-back exhaust and NOT computer programming mods if I wanted more gas mileage. Hmmmm. He said the CAI and exhaust has shown improvements in both gas mileage and some performance but that the computer programming really only helps with performance and can actually reduce gas mileage. Is this true?

[glennc]

Need a little more help here. An aftermarket dealer told me to just add CAI and cat-back exhaust and NOT computer programming mods if I wanted more gas mileage. Hmmmm. He said the CAI and exhaust has shown improvements in both gas mileage and some performance but that the computer programming really only helps with performance and can actually reduce gas mileage. Is this true?

[HUMMERcustoms.com/TAZ]

glennc the guy is being fairly honest with You. The programing though is not what will hurt You MPG it will be Your foot once You see the huge difference if You are running the more aggressive tuning. The different tuners come with usually 3 or 4 options from economy which will drive You nuts with all the shifting, i recommend the economy only on long travel with fairly level roads. They will usually have a stock type selection that actually has a few improvements. There will be a tow mode which My programming guy at Comp Cams recommended to run most time but, I went against that when I saw the power the perf. Mode gave. What You choose does change power and thus the lead foot factor. I ran a Comp Cams programmer that I loved and would still be running it if not for the Magnuson supercharger. Even in performance when i would keep my foot out of it most of the time and drive like a normal person I got 12.5 to 13 combined and got as high as 14.5 on the road. With supercharger I'm getting 11 mpg with self control but, I'm running 5 lb. boost tuning from superchips with no ability to lean it out and running so rich I tried a 2.75 pulley and it still runs solid rich. I think once I get My wideband tuning I will lean it out and improve the millage when I'm acting normal with My lead foot in check.
Do the exhaust Mod with a long kneck header for more low end torque, which is what the beast needs. I recommend it highly as well as air intake. I have other suggestions if You would like to PM Me. Most of these guys know what I will say as it has been discussed so no need to waste their time. But, would be glad to help further.
TAZ

[madcat]

Taz, I just hooked up an LC-1 "wideband"-o2 (WB02). I'm anxious to start tuning also! I'm running very rich also. Driving around with a laptop and seeing all the sytems work and then being able to adjust them is damn cool. Might have to start a new thread for this tho

[HUMMERcustoms.com/TAZ]

I picked up a sponsor for the show Queen that has written new tuning software so that You do not have to install a wideband sensor. it is on the way and after I try it out I will let You now more about it. It gives same tuning as good as wideband. You still use laptop but, I'm going to experiment with it for them and install it on the PC I'm going to get for H2 and load it on there and splice into the OBD2 port from the back so i can still run other tools on it and see if I can leave tuning software running all the time and just pull it up on the touch screen to check what is happening so I do not need laptop and extra person to help work out the tuning. I can do it by myself.
Will let You know more later.
They will also have a completely new platform in 4 to 6 months that will put others way in the back row and will let You know about it when it comes. They said in Our sponsor deal that I get the newest stuff before they release it and bugs already worked out of it to run it on the road for them. They have been great and respond to every phone call or email I make in short time.
TAZ

[glennc]

Very helpful and knowledgable advice. Thank you!