97 GMC Sierra 5.0l soon to get a full 5.3l swap..

[pacobeagle]

used an ecu mounting bracket out of blazer

now with ecu

[pacobeagle]

was able to finally turn the engine over. She'll run for all of 5-10 seconds and then shuts off. Mind you, the trans, and accesories are not hooked up yet. I mainly wanted to make sure that the engine spun and would start. The starter will have to be shimmed as it is making some crazy noise upon turning over.

Also, I may be having an issue with the stock 4.8l Y-pipe. I don't think it will clear the trans. crossmember. I'll update laqter on that. Sunday, I will have to trace any issues I'm having with the engine.

[pacobeagle]

Found out that my issue with the running is that famous "Security" issue. Apparently I have to override this somehow. Still looking to see if I have to ship ECU out to someone of if I can bypass it myself.

[notfastenuff]

Paco,
To my understanding, the only way to do it yourself is if you have tuning software like EFIlive. I've found quite a few people that will do it such as Neslon, Speartech, and even the guy over at the LT1 site with all the wiring info does it. I'd like to get the software to do it myself, but the cheapest I've seen the stuff to do it is around $600.

[pacobeagle]

Ok, I've found someone to do it for me. As a matter of fact, it's Lextech(a member here), that is going to do it. I'm also getting his A/C bracket kit. Hopefully, I should have this on the road within two weeks!

[silverado_lover]

[pacobeagle]

I saw your build thread, looks like it's going to be really nice. Plus, your truck looks great. I hope to get the outside looking as clean as that soon. Btw, what wheels and size are those. I like them.

[silverado_lover]

Thanks man, they're Cragar D Windows and the BFG's are 255/70/15. Next time I get new tires I plan on picking up some 18's...18x8 up front 18x9.5 in the back

[myzterray]

hey nice job man! hey what did you remove and keep from the original harness? im at the point in my build and im wondering what you integrated into the ls motor harness.

[pacobeagle]

It's somewhat complicated as I simply added a bus to my OEM fuse box and tapped into the power for all of the new items there. I also tapped into the OEM fuel power supply and ignition power supply from the fuse box. Essentially, I've still got the fuse box but with i think two or three added fuses. I can't remember right now. I've grafted both harness's into one. I've removed a bunch of grounds from the harness. If needed I can always add to them.
As far as keeping items from the OEM harness....I kept the starter signal, oil pressure switch, a/c, coolant temp, alternator wires. I also have to make a "y" harness for the speed sensor as it needs to go to the new ecu to deal with shifting the trans and it needs to go to old ecu for gauges. Theres more I'm sure, but my brain is fryed right now in dealing with al of these wires!!!!!