There’s a reason “LS swap” has become a verb. The GM LS engine family is lighter, more powerful, cheaper to build, and easier to find than almost anything else you could put in a project vehicle. It fits where a small block Chevy fits. It makes more power than a small block Chevy. And the aftermarket support is bottomless.
Whether you’re dropping an LS into a C10, a Camaro, a Jeep, or something nobody expected, here’s what the swap actually involves.
Why LS?
- Power density: A stock junkyard 5.3L makes 285–310 hp. With a cam and bolt-ons, 400+ hp on pump gas. A built 6.0 or 6.2 can make 500+ without breaking a sweat.
- Weight: An aluminum LS weighs under 400 lbs complete. Even an iron-block truck LS is lighter than the old small block it’s replacing.
- Availability: Millions of LS engines in GM trucks and SUVs from 1997 to present. Junkyard 5.3L engines go for $500–$1,500 all day long.
- Aftermarket: Every conceivable part — swap headers, motor mounts, oil pans, wiring harnesses, and accessory drives — is available off the shelf for the most common swap platforms.
- Fuel injection: Modern multiport fuel injection means reliable cold starts, consistent power, and no carb tuning. It just works.
Step 1: Pick Your LS Engine
Budget / First Swap: 5.3L Truck Engine (LM7, L33, LC9)
The most common and cheapest LS. Millions were produced in Silverados, Sierras, Tahoes, and Yukons. An iron-block 5.3 from a junkyard or a remanufactured long block is the easiest path into LS power.
- Horsepower: 285–310 hp stock, 375–425 hp with cam/bolt-ons
- Availability: Everywhere
- Price: $500–$1,500 junkyard; $2,000–$3,500 remanufactured long block
- Best for: First LS swap, budget builds, daily drivers, trucks
Mid-Tier: 6.0L Truck Engine (LQ4, LQ9)
More displacement, more torque, and the LQ9 comes with flat-top pistons and better-flowing 243 heads from the factory. A proven platform for 400–500+ hp builds.
- Horsepower: 300–325 hp stock, 425–500+ hp with cam/heads
- Availability: Good — from 2500 trucks, Express vans, Escalades
- Price: $800–$2,000 junkyard; $2,500–$4,500 remanufactured
- Best for: Builds where you want more torque than a 5.3, tow vehicles, street performance
Performance: LS1 / LS3 / LS6
The car engines — from Corvettes, Camaros, and GTO. Aluminum blocks, better-flowing heads, and higher factory power ratings.
- LS1 (5.7L): 305–350 hp. The original LS from the C5 Corvette and F-body Camaro.
- LS3 (6.2L): 430 hp. C6 Corvette and 5th-gen Camaro. Rectangular port heads with excellent flow.
- LS6 (5.7L): 405 hp. Z06 Corvette. LS1 with better heads, cam, and intake.
- Price: $1,500–$3,500 junkyard; $3,000–$6,000+ remanufactured
- Best for: Weight-sensitive swaps, sports cars, high-performance builds
Maximum: Stroker and Built Engines
A 5.3 block bored and stroked to 383–408 cubic inches, or a 6.0 punched to 416+ ci. Custom cam, ported heads, forced induction. This is where LS swaps make 600–1,000+ hp.
- Price: $5,000–$15,000+ depending on build level
- Best for: Dedicated performance builds, pro touring, drag racing
Step 2: What You Need for the Swap
Motor Mounts
Swap-specific motor mounts adapt the LS engine to your chassis. Available for the most common platforms:
Transmission
The LS bolts to several transmissions:
- 4L60E / 4L65E: The most common swap transmission. Handles up to ~400 hp reliably.
- 4L80E: Heavy-duty option for 400–700+ hp builds. Bigger, heavier, stronger.
- T-56 / TR-6060: 6-speed manual from Corvettes and Camaros. The manual swap choice.
- TH350 / TH400: Old-school automatics. Work with an adapter if you want to keep it simple and old-school.
Wiring Harness
This is the part that intimidates people, but the aftermarket has made it painless:
- Standalone harness kits ($200–$800) strip the factory harness down to only what the engine needs — no body control module, no anti-theft, no extra sensors. Plug in the engine, ECM, and a few sensors, and it runs.
- Factory harness modification — you can modify the truck harness yourself, but it’s tedious. A standalone kit saves hours.
ECM / Tuning
The LS needs its factory ECM (PCM) or an aftermarket ECM to run. Options:
- Factory PCM with custom tune: Use the original truck or car PCM and have it tuned for your application — remove VATS (anti-theft), speed limiter, and adjust for your sensors and transmission. $100–$400 for the tune.
- Aftermarket ECM: Holley Terminator X, FiTech, MSD Atomic — standalone engine management that doesn’t need the factory PCM. $800–$2,000+. Easier to set up but more expensive.
Oil Pan
The factory truck oil pan hits the crossmember or steering components in most swap applications. You’ll need a swap-specific oil pan:
- Muscle car swaps (Camaro, Nova, C10): Aftermarket LS swap pans designed to clear the steering and crossmember. $150–$400.
- Low-clearance swaps: Canton, Holley, and others make low-profile pans with kicked-out sumps. $200–$500.
Accessory Drive
The factory truck accessory drive (alternator, A/C, power steering) may not fit your engine bay. Options:
- Use factory truck brackets: Cheapest option if they physically fit. Check clearance to the firewall and frame.
- LS swap accessory kits (Holley, ICT Billet, Speedway): Clean, low-profile brackets designed for swap applications. $300–$800 for a complete kit.
- Delete A/C and power steering: For race/stripped builds, delete what you don’t need and run alternator-only.
Headers / Exhaust
LS swap headers are available for most common platforms. Long-tube headers make the most power but require more clearance. Shorty headers fit tighter spaces.
- Swap-specific long-tube headers: $300–$800
- Shorty / block-hugger headers: $150–$400
Step 3: What Does an LS Swap Cost?
Add $2,000–$5,000+ in shop labor if you’re not doing it yourself.
Common Mistakes to Avoid
- Buying the engine before the accessories. Make sure you can fit the accessory drive, exhaust, and oil pan in your engine bay before committing to a specific engine.
- Ignoring the wiring. Don’t try to “figure it out later.” Buy a standalone harness kit or have your wiring sorted before the engine goes in.
- Keeping the old torque converter. If you’re using an automatic, install a new converter matched to the engine and transmission. Old converters are worn and contaminated.
- Skipping the tune. An untuned factory PCM will throw codes, keep the speed limiter active, and may trigger VATS anti-theft lockout. Budget for a tune from day one.
- Wrong flywheel/flexplate. LS engines use a specific bolt pattern and pilot bearing size. Don’t assume your old-school small block flexplate fits — it won’t.
Where to Buy the Engine
Bishop Car Parts carries remanufactured LS engines — 5.3L, 6.0L, and bare blocks ready for custom builds. Whether you need a stock-replacement long block or a machined bare block for a stroker build, we’ve been specializing in GM powertrains since 1948.
