If I can do it, you can do it! I have taken the EFI plunge and survived. Like many of you, I was/am not very savvy with electrical gadgets, wiring, or fuel-injection systems, but luckily there are people out there who are and make parts to help the electrically challenged.
This is the finale of our series on how to install a Chevy LS engine into your truck. The truck used was a '72 Chevy C-10, but most of the install is as universal as possible and outlines the parts or type of parts you need to do it yourself. This was even done with an '01 Chevy Suburban 5.3L iron-block engine from a wrecking yard. In fact, the owner of Dave's Goldenwest Truck, where I got mine, says he's now selling these engines for $500, which is perfect for those with more time than money. This should leave the remaining budget to buy the new harness from Turn Key Engine Supply and the rest of the parts you'll need. Listed in the source box in this article are all the companies I got parts from, excluding auto parts/hardware/electrical supply stores for miscellaneous pieces that will vary truck to truck and also depends on your truck's current condition.
There are several books available on LS engine swaps and people have been doing them since these engines came out in the late '90s, but we haven't seen any in-depth how-to articles pertaining to older trucks. Hopefully, these four stories will help those thinking about or scared to take the plunge into a modern EFI conversion. In fact, if you are handy and can do the work yourself, you should be able to do the whole swap for less than most new small-block crate engines cost. Not only that, but you'll have reliability, a lot better fuel economy, and last but not least--power! The C-10 still needs exhaust, but we did one easy dyno pull and got almost 260 hp and 280 lb-ft of torque at the rear wheels! Not bad for a stock junkyard engine. Plus, it's no secret that LS engines are easy to squeeze more ponies out of and a cam and head swap can easily put power figures between 400-500. After a short and loud drive in the '72, I will say that 260 hp to the pavement is plenty for most people!
All in all, the swap went well and the engine looks almost like GM put it there when you open the hood. Throughout the series I've tried to outline any issues or concerns that I had so you know what you are in for. The other installments are in the March, July, and August '09 issues of CLASSIC TRUCKS. After some seat time I'll report on fuel economy and how much fun and driveable I'm hoping the truck will be. My best advice is to take your time with the work surrounding the swap and do it so you'll be happy with it for years to come.
 It's no secret that most any...  It's no secret that most any electrical system needs good leads and grounds--especially with EFI engines. I'm not proud of it, but this was the main power wire coming off the battery to the fusible link--not good, let alone pretty. In the end, I spent a good deal of time replacing much of the stock engine bay wiring from scratch. |  During the process of figuring...  During the process of figuring out the "modified" stock wiring, we put too much juice through the system and melted the OE fusible link, which is what it is supposed to do. Instead of installing another one after the wire cooled, I cut it out and replaced it with a modern 30-amp MAXI fuse. This will be easier and safer to replace in the future, should the need arise. |  The MAXI fuse holder mounted...  The MAXI fuse holder mounted on the inner fender where the fusible link was and cost under $20 at the auto parts store. Pick up an extra MAXI fuse while you are at it. |
 Now that the wiring was back...  Now that the wiring was back to ground zero, I could start in on the wiring. I decided to run a 10-gauge power wire from the alternator to the power terminal on the starter to simplify things instead of finding another key switch power source. I like to use uninsulated terminals and adhesive-lined heat shrink for a more professional and clean look. |  Here we are down at the starter...  Here we are down at the starter and the red wire is from the alternator and going to the battery power post. The other wire is from the ignition and is going to the starter solenoid post. |  The harness from Turn Key...  The harness from Turn Key Engine Supply uses many other "weather pack" connectors that are already part of the harness, but there are five that need to be crimped to connect a few things. The two gray ones are for incoming constant power to electric fans and the three black ones are for key-switched power to the ECU, power to the fuel pump, and the tachometer connection. |