Here are the latest products to help you swap an LS motor into your classic Chevy. Back in 2009 when LS swaps were gaining ground, we had Mike Copeland write an in-depth story on the things you need to consider when swapping an LS engine into a vintage muscle car. Mike was the project manager for the Performance Vehicles division at GM then, and is now the operations manager at Lingenfelter Performance Engineering, so he knows a few things about the LS platform. Fast forward just a few years and the aftermarket is in high gear, producing a lot more products to support such a task.
It was time for us to bring that story up to date and also show y'all where to get the latest and greatest products for the LS. We have broken the story up into specific sections like wiring and exhaust that will highlight the things you need to consider and the products that are available.
First off, you need to know where you can actually get the LS motor for your swap. Obviously a wrecking yard will be a good place to look for used engines. Try and pick up the computer, harness, and gas pedal if at all possible. If you go that route, make sure the yard offers some sort of return/exchange policy just in case your engine turns out to be broken. If you would rather have something new, then you will need to contact an aftermarket company. Chevrolet Performance has crate versions of just about every LS available, from the simple LS1 up to the badass supercharged LS9. Not to be outdone by Chevrolet Performance, there are places like Mast Motorsports and Pace Performance that will sell you a complete LS engine ready to go. If you want to build one from scratch, look to Lingenfelter, Dart, RHS, and Chevrolet Performance for short- and tall-deck blocks. These allow you to build LS-based engines all the way past 500 cubic inches.
Chevrolet Performance, like we mentioned earlier, has the entire LS family covered and is really proud of its eco-friendly E-Rod program. In a nutshell, the E-Rod package is a crate engine combined with engine wiring harness, engine control module, exhaust manifolds, catalytic converters, oxygen sensors and sensor bosses, fuel tank evaporative emissions canister, mass airflow sensor and sensor boss, accelerator pedal (for use with the electronic throttle), air filter and instruction manual. The highest horsepower E-Rod package right now is the LSA. It's the engine out of the Cadillac CTS-V series of high-performance vehicles. Using an advanced, highly efficient four-lobe supercharger, the LSA 6.2L engine is rated at 556 horsepower.
Pace Performance designed this little Screamin' Mimi engine package using GM's 4.8L truck engines. The dyno-tested package made 300 horsepower and 340 lb-ft. This engine only requires a two-wire hookup to run, timing is preset (but can be adjusted), does not require oxygen sensors, and runs on low 5-7 psi fuel pressures. It comes with a 12-month limited parts replacement warranty.
For the LS guy who wants something really gnarly, check out Dart's LS1-style billet aluminum block. Machined on precision CNC equipment from a solid billet of 6061 aluminum, the Dart LS1 block offers virtually unlimited choices in deck height, cylinder bore centerline, bore diameter, and lifter/cam configurations. The Dart LS1-style billet block is available with or without water jackets and can be ordered with additional head bolts, custom motor mount bosses, and optional camshaft diameters.
Flexplates & Flywheels
The rear snout on the crankshaft on all LS-series engines is 0.400 thousandths short compared to traditional small- or big-block Chevy engines. If you are using an LS engine/transmission package, there is no issue. If you are installing a traditional GM transmission on LS engines, changes must be made to locate the flywheel or flexplate in the correct location.
Engineered to prevent cracking and ring gear breakage commonly found in lesser-quality flexplates, this new design includes an integrated early-style GM torque converter pattern that gives the option of using an LS-series or earlier model transmission with LS engines, including the LS9 or LSA. In addition, the precision-ground, 3⁄16-inch-thick A36 steel plate material is 0.067 inch thicker than the original factory piece, which makes it stronger. Finally, the most important feature is that these performance flexplates have been tested and are SFI 29.1-approved for strength and durability.
The APS starters from MSD feature a 3.4-horsepower motor powering a 4.4:1 reduction gearset to deliver great torque—enough for 18:1 compression racing engines. Inside the compact housing, MSD put two ball bearings to guide the balanced armature through countless smooth engagements and starts. Another handy feature is that the billet mounting block can be rotated in different positions to help clear oil pans and suspension parts.
There are a number of production-based intake manifolds, as well as a multitude of aftermarket units. The LS1, LS6, and truck manifolds interchange, but the truck manifold is pretty tall so it might pose a hood-clearance issue. These engines share a common intake gasket design. The LS6 intake is a popular upgrade for LS1 engines and adds 10-15 horsepower. If you are looking to keep the system a bit simpler by running a carburetor, you are in luck as there are a few intakes offered that allow the use of a carb.
The newest thing in the LS intake market is Holley's GM LS3/L92 Modular Hi-Ram-style intake manifold. Coupling this Hi-Ram intake with the high-flowing LS3/L92 cylinder heads has outstanding potential for N/A and forced-induction applications at a budget-minded cost. The base is designed to be modular in configuration to accept a wide range of carbureted and EFI tops and to be attractive to builders and fabricators as the foundation for custom induction systems. EFI fuel rails feature -8 fittings with passages large enough to accommodate high fuel flows and dampen pressure pulsations in the fuel system and come standard with EFI Hi-Ram-style kits.
Holley Performance Products
Reluctor Wheel Identification
Currently, there are two generations of reluctor wheel in the LS family. What's a reluctor wheel? A reluctor wheel is part of the ignition system. Much like a crank trigger, it (combined with a sensor) tells the ECU what position the crank is in, so it can fire the coils off at the correct time. The easiest way to determine which version is which is the location of the cam sensor. Gen-III engines have the cam sensor located in the block at the rear of the intake manifold. Gen-IV engines have the cam sensor located in the front cover. Also, Gen-III engines have 24X crank sensors, and Gen-IV has 58X. The 24X sensor has a black connector, and the 58X has a gray connector. Engine controllers must be matched to this sensor or the engine will not run.