How To Do a 5.3 Swap on a Budget

Regardless if you’re at your local car show, rod run, or if your just driving down the highway, the odds of seeing a car that has an LS swap in it is very high. With the large amounts of power these LS engines have and the great reliability and fuel mileage, makes these engines very popular for everything from a Mustang to old roadsters.

LS swaps can get pretty pricey, but we found an article written by MeanYellowZ on LS1tech, that tells you how to do a LSx swap for cheap.

The engines that the author refers to in his article are the 4.8, 5.3, 5.7 and 6.0 engines because they share the same platform and most parts with the actual 5.7 aluminum LS1 engines. He rarely does actual LS1 swaps because you can go to a junkyard and buy a 5.3 for anywhere between $250-$550 and that is complete, minus the starter, alternator, power steering, etc. The only difference between the two engines are the actual LS1 has an aluminum block which ways 65 lbs lighter than the 5.3 and it makes around 10 hp more, but an actual LS1 will cost upwards of three times more than the 5.3.

Images from

The next biggest expense in the swap is the wiring harness. With the harness you have two different options to choose from, either the truck harness or the harness from a true LS1 car, like a Camaro or Firebird. The differences are in the injector plugs and the way they lay out. Besides choosing what harness you want to use, another big choice you have to make is if you want to go with the ‘ugly’ truck intake that still makes good power, or if you want to switch to the car style intake, fuel rails, and fuel injectors to make it look more like an actual LS1.

Next is the transmission. The LS engines will work with any older GM transmission with a few things to consider. TH350s/ 700R4s/ TH400s work by using a flexplate spacer and bolts for proper offset. Using an automatic transmission will work, but they are harder to mount up than an older manual transmission with the proper bell housing that should be easily available at the junkyard.

The last things to consider are the fuel system, alternator, and exhaust manifolds. The fuel system can be purchased all over the net, and that would be a great way to go if this wasn’t a budget swap. You can pull your factory sending unit and find a way to mount the pump to the sender and install in tank, or search for a vender that makes a sending unit for your application to do just that. Other options you could go are to weld a sump to the bottom of the tank and feed your pump from there, or to find a fuel cell and install it. A good alternator to use are the GM CS-style alternators that are found on 4.3, 5.0 and 5.7 engines.

The exhaust manifolds may be the hard thing to come by, but that is all depending on your application. If your vehicle does not allow you to use the stock LS style manifolds that fit your chassis you may need to search for ones that do or possibly find aftermarket headers.

LS swaps are highly sought after, but a lot of people are discouraged in actually attempting the swap because they think it will really hurt their wallet. With this guide to a cheap LSx swap, it makes it virtually easy and inexpensive to shove an LS engine in anything you can think of.

About the author

Andrew Wolf

Andrew has been involved in motorsports from a very young age. Over the years, he has photographed several major auto racing events, sports, news journalism, portraiture, and everything in between. After working with the Power Automedia staff for some time on a freelance basis, Andrew joined the team in 2010.
Read My Articles

Late Model LS Power in your inbox.

Build your own custom newsletter with the content you love from LSX Magazine, directly to your inbox, absolutely FREE!

Free WordPress Themes

We will safeguard your e-mail and only send content you request.