mods and tunes questions
 

Ok, I have had a love affair with Duramax diesels since my dad got one of the meanest trucks you've ever seen (an 01 LB7 dually) when I was a kid.

The link is to a video of that truck pulling a semi out of the ditch,
Anyway, I have have been around them all my life and my family has had a few of them over the years, but have never been able to justify spending the money on one of my own... well I have a bit of a Craigslist addiction, and happened to find an 01 GMC ext cab long box, LB7 for $5,000. Well, lets just say I justified it.

The truck is in great shape, fully loaded, heated leather, blah blah, super nice. But it has 256,000 miles on it. It doesn't really scare me, driven mostly highway, I am the third owner, fires right up even in our bitter MN winters, still has all the power it should have, Posi still works great, so great the truck will whip sideways on dry tar and hit 90mph by the end of the on-ramp:jump:.

That being said, the truck is bone stock. Stock exhaust, no tuning (that I am aware of), stock intake, etc etc. Now I have an internal practicality vs performance battle going on inside of me.

I really am considering exhaust and a tuner, possibly CAI. I know when my dad went to 4in exhaust he gained about 2mpg and the sound... oh the sound. He has a predator progammer that is about a decade old now, which has a few preset tunes (40-60-100HP+) and I know at 40HP+ he generally gets a little better fuel economy.

Well, since the days he bough his little plug-in tuner, things have gotten a bit more complicated, EFI Live, PPE, edge, Bullydog, etc. and exhaust seems to be spendy, intakes are spendy... yeah, I know, it a diesel.

So my ultimate question is this;
What is the best bang for a daily driver buck? Most interested in power that boosts econ as well. Keep in mind its a truck with a 1/4 million miles on it. If I could get some detailed info on what experience people have had with the various budget mods, and what kind of returns they have gotten.

Thanks in advance and sorry for the long post.

to me this sounds like it already has a tune.

if it was me i wouldn't choose anything but Efi Live. best potential for power and MPG. if you dont have an upgraded transmission i would keep the HP upgrades below 60. any higher and transmission life is severally reduced

exhaust upgrades are good. helps lower EGT

i would skip getting a CAI, over rated. instead mod your own: https://www.dieselbombers.com/01-04-...e-box-mod.html

Thanks for the info.

This brings me to my second question about EFI live... Basically, what is it? I know its a software system that lets you set tunes on your truck. But what is all entailed? Should I buy the software myself and do it or take it to someone? If i do it myself what do I need besides software? There is a guy selling a laptop with a bunch of different tunes already on it for $300. Is this a good way to go or not?

EFI Live is basically a computer to OBD port interface with accompanying software.

you plug the cable into the OBD port of the truck and into a USB port on the computer. with the software you extract the "tune" from the ECM or TCM, whatever you are trying to modify.

the software will have the tune separated out into a bunch of tables and charts. these charts and table are what the ECM uses to determine how much fuel, timing, RPM, etc to apply and when.

you will, or a professional tuner if you decide to purchase one, modify the values in these tables to create your own tune. using the interface cable you reload this tune into the ECM and enjoy, or if you messed it up curse the new performance.

it is a long learning process that takes many hours logging, tweaking, etc to create safe and smooth tunes yourself. it may take years before you start to get proficient at it and then you may still not know what you are doing.

if this is something that sounds like fun i would say go for it. if not purchase from a pro tuner.

check out there site for more info: https://www.efilive.com/

if this laptop comes with a V1 or V2 cable and unused license then that looks like a good deal. i would not use the provided tunes as they may not be compatible with your ECM. the best way to do it is to start out with the stock tune from your own truck or at least one with the same OS number