I have a os system that is otherwise unique to the tuning world, I have been through many different options to tune my truck with Justin a black Bear Performance there walking me through the steps.

I started out with the 6.0 swap and had to find a OS for a 6.0/4l60 to work, Justin made it work.

Then i went turbo with the same engine/trans combo and it was fine on 3 psi but i bumped to 7 and the maf went crazy, shortly thereafter i killed the 4l60 so i swapped to an 80 for yet another segment swaped OS for justin to find.

All said and done the maf tune with 7psi just wouldn't cut it, the driveability was horrible and not to mention it just didn't feel right. So i was careful with that tune and tried to make it work until i could figure somthing out.

I spoke with Justin last week about doing somthing that hasn't been done yet. I was dead set on have a Custom Operating System for my truck and many people said that can't be done even on the efilive forum. So Justin got to work and came up with a list of things i needed:

03-04 pedal and tac module
and harness from pedal to module
2 bar map from gm


He wrote a cos3 tune for the truck using a 04 os and 2500 hd as the base and after several hours of me and nonnie cruising around we started getting the truck dialed in, Its still not perfect, there are a few details that I think need to be fixed but for others it would be perfect. I am very picky about how the install looks and functions and so i have some fine tuning to do and clean up the older pedal but every thing is plug and play. So any of you guys thinking about doing this feel free to pm me if ya have any questions. I will get pics soon of the new stuff! and hopefully have some track times Sunday afternoon!

 

You can do a 2bar speed density tune rather easy on that OS. No custom os needed. Dozerdans truck was this way and driveablity was like stock. Sounds like you have things going good though.

 

Justin is the MAN!

 

Dang man you shoulda searched my name or asked. I searched this for truck because I wanted a custom os too. But since Tyler is such a badass we didn't need it

 

haha i was at a loss man! I felt like a searched everywhere and never could find anything but now its great! I am so happy with it and its actully fun to drive, i just want to go drive and race people(yes including gradma's with the buicks ) !!!!

 

How much were the parts and where did you get them if you mind me asking. I'd still kinda like to do it for easy of tuning if I ever went back to FI. You can pm me if you'd like

 

lownslo, post up prices/ source if u don't mind. It's really cool u got it figured out.

 

I picked up the pedal, tac module and harness at a junk yard and i ordered the 2 bar map sensor from gm p/n 12580698. It was about 55 bucks for the map sensor.

I have less that 120 bucks total so far for the entire swap(parts alone)

It is very straight forward to install. Replace the pedal by removing the old pedal and bracket and put the new pedal on the floor, replace the tac module and run the harness through the firewall, plug it up and install the 2 bar map on the intake manifold and load the new tune with cos3 on the 1mb pcms.

I hope that helps you guys!