Sourcing LS Engines: A Helpful Guide to Finding “The One”

So, you’re married to the idea of buying a LS engine to swap into your ride. Except, you’re not sure where or what to look for. Well, today that’s what we’re going to talk about. Sourcing LS engines is almost like flipping rocks and looking for bugs—success is imminent. Though, having some helpful tips will take you a long way. For that, we returned to our good friend and master of all-things-LS-swap, John Potucek, of Keystone Automotive.

One Man’s Trash…

When it comes to sourcing LS engines, most of us are going to start by looking for a second-hand engine. Why? Well, why not? Sure, you can go ahead and buy a crate LS engine for a pretty close price point to what you’re going to spend building one. But here’s the thing: the aftermarket is abundant for these engines and, when it comes to build tactics, the sky is the limit. By buying an engine for a build, you can take it wherever you want.

The bottom ends on these engines are stout and have a very long lifespan. This generally means that you can make out very well with the low-buck purchase costs associated with buying one of these engines pre-owned. But, where to start?

Potucek offers some advice, urging LS shoppers to ask themselves a few questions—like, are you willing to pull the engine yourself from someone’s driveway or a junkyard? Or do you need one that’s already been pulled. “And I say someone’s driveway, not because I’m telling you to go around popping hoods and stealing engines, but because one of my secrets is to search for people parting out trucks,” explains Potucek. “Let’s say the transmission went bad and the truck sits in a person’s driveway. If they’re not a car person, they likely have no idea about [or plans for] the engine. That’s where I’ve gotten the best deals. We’re talking a $300 L33 or 6.0—but you have to be willing to pull them where they sit. If you’re good at searching Craigslist and Facebook Marketplace, that is the key!” adds Potucek.

In addition to online avenues, local junk yards, the nearby U-Pull-It, and your newspaper’s classifieds are also great resources when sourcing LS engines.

How do you know you’re buying good quality?

How many of us have used second-hand speed parts only to find there’s a reason someone was getting rid of them in the first place? Yeah, that’s a good way to get burned and leave a fowl taste in your mouth. So, what can you do to save yourself this experience when sourcing LS Engines?

“If I’m buying from Craigslist or Facebook Marketplace—likely from someone parting a truck out—I usually like to hear it run,” advises Potucek. “If I’m buying it from a U-Pull-It or junkyard, I look for a vehicle that was in an accident. Otherwise, it’s likely the vehicle made its way there because of the engine. Additionally, I will sometimes go against logic and buy one I can’t hear running, as long as it spins over and feels to have compression. I’ve bought and sold probably 50-60 LS engines in the last 4 years and never had one person come back and complain, so I must be doing it right!” he adds.

Do Your Homework

Having a build plan in mind (or at least a rough idea of your end goal) is important before you start shopping. This will help you sort through options, and keep you from spending unnecessary money. But, generally speaking, what should you be looking for?

“I always say: buy the most complete engine you can afford,” says Potucek. “If you buy one in pieces or one that’s missing pieces, just because it’s ‘a good deal,’ chances are it’ll nickel and dime you in the long run.”

Additionally, travel is an important factor to keep in mind when sourcing LS engines. “How far are you willing to drive?” asks Potucek. “I see killer deals on LS engines but they are 3 – 4 hours away. Sorry, but I’m not doing an 8-hour round trip. Generally, two hours each way is about my limit for the right deal.”

A low-buck budget can start to climb fast if you opt to travel far for an engine. Consider the truck you’re using to haul it, the gas, supplies, snacks, etc… Now, factor in the added weight on the way back—which means you’ll be spending more money on gas—and you’re easily looking at an additional $100 or more just in travel expenses.

And, don’t forget, if you’re driving this far for an incomplete engine—those hidden costs Potucek mentioned before also stack onto the balance. Ultimately, with LS engines being so prevalent, it’s likely you can find something local. (And it’s worth your time to try.)

It’s also important to keep an open mind when shopping. Potucek usually targets late-model pickup trucks, as his favorite engine is the L33, which is pretty rare. (It was only made for three years, 2005-2007, and was only available in extended cab 4×4 1500s with VIN B, the H.O. engine package.) Therefore, in Potucek’s case, when he’s looking for “The One,” he’s paying attention to VINs. However, he’s still willing to adjust based on what looks good. “I’ll take any 2004+ 4.8, 5.3, or 6.0. They’re all good platforms to start with, so if the price is right, I’m not greedy.”

What’s a fair price?

As you can see, the doors are wide open when sourcing LS engines. Though, we do need to take a look at one more thing before closing the conversation: Pricing. What is a good deal? Are LS engines so special that you should expect to invest a lot of money in a second or even third-hand engine?

“At U-Pull-It yards, they don’t care what engine you’re pulling—at least the ones I go to. That means, it’s a flat price for the engine,” explains Potucek. “At yards that pull the parts for you and inventory them, the prices will be higher.”

Potucek says that, on average, from a general U-Pull-It, he pays around $230 total for any engine. (Obviously, this number will vary, depending on where in the world you live.) “On Craig’s List and Facebook, I can typically snatch them for $200-$400. The key is being in the right place at the right time. When those deals pop up, they’re gone quickly.”

That said, if you’re in the market for an LS, it’s a good idea to know what you’re looking for and be ready to move fast. If you’re on a budget, keep in mind that this is but one aspect of the process. The build is going to cost even more when you’re ready to start that step. Not to mention, when you do crack the pan open, you might find some work for the machine shop. Your best bet is to do the research and be diligent during your sourcing process, in order to ensure you get the best deal.