How to get started ??

[Lennart]

Here is what I want to do:

Truck:
2000 GMC Sierra with 5.3l OS:09381344


We are in the process of installing a Whipple charger without the piggyback electronics but using 42# Delphi injectors.
I understand that there are multiple ways to get the truck running...starting with the current OS modified for FI to an 2002 OS5 custom OS.
At holdencrazy.com I found a 99 OS tuned for a Radix which I plan to use a a baseline to get started.
Until now I do not have a wideband O2 sensor, something I will probably need to get the charger dialed in properly.

In which order shall I proceed?
- Copy the changed tables from the 99 Radix to the 2000 OS?
- Go straight to the OS5 by flashing the 12212156 OS with the 99 Radix changes and the 2000 content? I understand we will also need the 2bar MAP sensor....

Primarily I want the truck to run in the first place and be safe on the tuning side not to run too lean....

Thanks,
Lennart

[dfe1]

Ultimately, you'll have to flash in a custom operating system to use the 2-bar map sensor, so I'd start there. You don't particularly need COS5, COS3 also has the capability of running 2- or 3-bar sensors. I'd switch to whatever COS you want, and get the tune close with the 1-bar sensor (obviously, you'll need to stay out of boost). That will eliminate the MAP sensor as a variable while you're trying to get AFR dialed in. Once you have part throttle AFRs close, switch to the 2-bar sensor and re-tune part throttle, no-boost operation. After that's close, you should be able to move on to WOT and positive pressure tuning fairly smoothly. If you change everything at once, and run into problems, you'll wind up doing a lot of unnecesary tail chasing.