Around here we have a couple options. First is to take the vehicle with the LS/LT engine installed and the 4L60/4L80 transmission along with the factory harness to a place like True Street in McKinney, Texas and have them re-flash the computer to delete all the stuff not needed; like anti theft, etc. Runs <> $600. Another route is to replace the factory do everything set up with an after market unit; $1000-$1500. We have had good results with FiTech units but Edelbrock and Holley ones also get good ratings. The FiTech throttle body unit is self tuning which is good for low techs like myself. Does require the above mentioned FI fuel pump and an O2 sensor bung welded into an exhaust head pipe. A picture of each set up:
Factory set up in a 49 3100:
[img]https://i.postimg.cc/0zZQKfKJ/IMG-4398.jpg[/img]Computer and relays mounted:
[img]https://i.postimg.cc/14C4zM6n/IMG-4389.jpg[/img]Aftermarket Holley LS FI in a 54 3100:
[img]https://i.postimg.cc/w18d0sLT/IMG-4838.jpg[/img]FiTech LS FI unit in a 70 Blazer (ignore the Edelbrock coil covers):
[img]https://i.postimg.cc/crH51YwB/IMG-5001-1.jpg[/img]
