LS Swap Planning Tips: More Power, Less Headache

I won’t waste your time by talking about why an LS swap is a good idea. You already know the benefits that come with running this engine platform, thanks to their performance potential and economically-friendly stance. Besides, when rolling around the idea of an engine swap, “Why?” isn’t usually the brain-buster question. It’s “How?”

As usual, when it comes to all things LS, we’re turning to our good friend John Potucek of Keystone Automotive. You may remember John from our previous coverage of the LS engine, as well as the spotlight we did on his sweet track-ready 1973 Chevy Nova, which sports a turbocharged 5.3 LS under the hood. He has a lot of love for the LS platform—and plenty of hands-on experience to prove it. We even hear he has plans in the coming months to LS swap a C5 Corvette. (Something we’re very excited to report on as his plans progress!)

Craft A Road Map

Last time we talked LS, we stressed the importance of thinking ahead. Anytime you go into an automotive project, this is a critical step. But when it comes to swapping an LS—specifically into a vehicle that never had this engine as an option—the planning stage is extremely important.

Before you begin, Potucek suggests asking yourself a few questions:

• How much room is under the hood of the car?
• Did it come with a V-8 or 4-cylinder?
• Are there resources online showing other LS swaps for the same model vehicle?
• Are there aftermarket kits available?
• Is this your only vehicle?
• What transmission do you plan on using?

Furthermore, if you really want to accomplish this task, then familiarize yourself with the drivetrain platform of choice and any special characteristics of it that will shape your process. Luckily, the LS isn’t exactly some space-age piece of machinery that’ll drive you too far up a tree.

“I don’t think there are any obstacles unique to the LS swap that other swaps wouldn’t have,” says Potucek. “Actually, the LS engines are so popular—and there is so much support from the aftermarket—that they are probably at the top of the list for easy swaps. In fact, they’re so easy that they often upset many ‘purists.’ It always makes me smile seeing someone get upset over someone else’s decision to do an LS swap. I’m sorry that I like cheap, reliable horsepower and you enjoy doing everything the hard way,” he quips.

It’s true that LS swaps are easier than most—but any engine swap is going to require an advanced level of automotive expertise. It’s not the sort of project you just jump into. This is especially true if there is any level of fabrication involved in the process.

Pro Tip: Don’t forget to include engine wiring in your planning process. We’re currently drafting a guide on this very topic—so stay tuned!—but suffice it to say, you’ll save yourself a major headache by plotting this out ahead of time. You have some options, like reworking the donor harness. You can also purchase a new harness, set up for LS engine swaps. Painless Performance sells such standalone harnesses (i.e. a harness that runs the designated engine and transmission only).

Know the Variables

“Some swaps are easier than others. Either way, make sure you have some type of fabrication skills or money,” says Potucek. There is no one-size-fits-all with an engine swap. The level of difficulty and amount of planning is heavily dependent on the vehicle it’s going into.

Generally speaking, planting an LS drivetrain in a front-mounted, rear wheel drive vehicle will be your easiest route. Let’s say you had something like a 1969 Camaro—a lot of your work is already done for you. Though, if you’re fitting an LS into a front wheel drive vehicle that originally came equipped with a smaller engine, you’re going to be spending way more time modifying the vehicle to make this work.

In any case, you need to be honest with yourself and leverage your skills against your budget.

Granted, what’s in your wallet will ultimately dictate whether or not you approach this in the first place; but knowing the limit of your capabilities is equally important.

If a swap requires you to reshape the vehicle in any fashion, like converting front wheel drive to rear wheel drive, or chopping and reshaping a firewall to make room for the engine and transmission, you need to determine sooner rather than later if you’re up to the task.

“Sure, there are times when I wish I could buy a part or pay someone else,” admits Potucek. “But, for me, it’s often a better option to fabricate what I need, myself. Plus, I feel like there’s a certain level of satisfaction at the end of the day knowing I did that. I have a few projects I’ll be tackling in the upcoming months/years, one being an LS-swapped G35. I started the research stage and looked at pre-fab kits but just couldn’t justify the price tag, so on that project, I’ll be doing my own fabrication work.”

Keep fuel delivery in mind.

While getting the engine in is your primary goal here, let’s not forget that plumbing is a concern, too. Depending on the application, different brands and different products will suit your needs.

For more extreme or high-end applications, a brand like Aeromotive, who supplies competition-level fuel pumps and fuel cells, can’t steer you wrong. Since we’re talking about physical fitment, fuel cells are the best solution if your factory fuel tank just won’t cut it. Once you get that fuel cell in place though, you’ll need high-quality, reliable AN-fittings and plumbing solutions to properly route fuel to the engine. We recommend you turn to a brand like Aeroquip. As the only leading performance plumbing supplier that engineers and manufactures its own hose and fittings, you can rest assured you’re getting a quality product with 75+ years of experience behind it.

As you begin running fuel lines to the engine, unless you follow the exact route from the factory, it’s almost guaranteed you will have issues of the fuel coming too close to the exhaust system and other components. Throw a bigger exhaust in the mix, plus headers, and suddenly that problem inflates. Let’s also not dance around the fact that, when you’re cramming an LS into a vehicle, low speeds aren’t always on the agenda. In fact, you’ll likely be spending time at the track. This means that accidents are a risk.

While hot fuel is less-than-desirable for performance, it’s also a terrible contributor to living conditions. There are all sorts of ways to reduce fuel temperatures and reduce the risk of fires breaking out. What’s the simplest step you can take, though? Adding a layer of protection to your fuel lines.

Consider using Aeroquip’s Firesleeve for added protection. This hose flame-shield can prevent (or delay) hose lines from burning. Fire Sleeve features a durable rubber coating resistant to abrasion, tearing and, above all, flames. Ordered by the length, it simply slips over the fuel hose you wish to protect. It’s simple, it’s effective, and best of all it’s made in the USA.

You might be tempted to go with a cheap option to save some money. Just remember that a fuel line burning up, popping, and dumping fuel onto an open flame is what we’d call a serious problem. You need a product you know is going to work no matter what. So really, is there any other option than Aeroquip?

Common Swap Solutions

It’s worth reiterating that John Potucek is no noob. He has skills and experience that allow him to fabricate and assemble exactly what he needs to complete his builds. This, inevitably, saves him time and money.

If you feel your own fab skills aren’t up to snuff, or you simply have no interest in taking on that job, there are still plenty of options for you to get the LS swap of your dreams. Numerous aftermarket suppliers cater to enthusiasts just like you.

Trans-Dapt Performance is a popular brand providing complete engine swap kits, including application-specific headers and mount kits for iconic rides like 1st and 2nd Gen Camaros and Firebirds, Chevelles, El Caminos, GTOs and other 1964-81 A-Body cars, C10 trucks, S10 trucks, as well as GM X-Frame, X-Body and G-Body cars. They also supply what they call “more flexibly-designed products” for uncommon combinations, including close-fitting LS swap cast manifolds and universal LS swap engine mount kits.

You can check out their “Swap-in-a-Box” Kits here.

There are several other brands who answer the call for oddball LS swaps as well, like Muscle Rods, who is a great source for planting an LS engine in a Fox Body Mustang.

These kits are great because they provide you with the engine and trans mounts, oil pans, exhaust headers, and other necessary odds and ends. In fact, Potucek points out that even if you don’t plan on using an aftermarket kit, just looking into one as a sort of ‘LS swap planning guide’ can be immensely helpful. Plus, you can look at these suppliers as sources for individual components that you may not be able to fabricate yourself.

Remember…

Keep in mind that these kits are not the be-all-end-all. You still need to consider what driveshaft will be made for your particular application—something for which you’ll need to keep a shop in mind.

Besides, what about getting the engine running? While an LS is simple in terms of late-model performance, you still need to get the thing to do more than sit pretty in the engine bay. Potucek suggests Holley EFI for an engine management solution. “Honestly, with the new Terminator X line-up they recently released, it’s a no-brainer. So easy to use and learn—even if you have no prior knowledge,” he says.

Plan, Plan, PLAN

Again, the most important aspect of tackling that LS swap is really figuring out the particularities of your build. Comprehensive, pre-fab kits can be a godsend for many builders. But before you go installing parts, ask yourself how it will play into the overall build.

You may find yourself looking at a swap kit saying, “These are great but I didn’t plan on using that transmission,” or “Wait a minute, this won’t work with the turbo I want to throw in there.”

As we always say, do your research. Be diligent in your engine and parts sourcing process, and keep revisiting that build plan! Obstacles crop up, new ideas come to the table; you want to have an organized way of addressing them.

Wondering how to make a specialized setup work for an uncommon LS swap? Check back soon, as Potucek isn’t done sharing his wisdom.