How To Swap A Gen III Engine Into A '64-'72 A-Body

The idea is to get the large hard-parts into the car, then follow up with the details, like dialing in the transmission electronics, the fuel injection, and tidying up the lists of all the little components beyond the scope of this story. The '64 El Camino still had the original 283 V-8 that smoked like the stack at Burger King. We shoved the powerplant into a corner for a rebuild later.>>>

Over the last two or three years, we've noticed the price for a Gen III V-8 has dropped from $5-6K to as low as $1,500 for a 5.3L engine and transmission from a pickup truck, and $2-3K for a 6.0L from a crashed van or Escalade. Aluminum LS1 engines from the Camaro/Firebird are also dipping into the $3,000 zone. We even pulled a truck engine from the yard and built a 480hp 6.0L for less than $3,800. But up until now, we've never tried to put one in a car.

We were told our engine was from an '04 GTO, making it an LS1. We ran the digits on the block and discovered that 12561168 is an LS6 casting number, and the 241 stamped on the head and oval exhaust port meant the heads were from an LS1 (LS6 ports have a D shape). Regardless of where you source your engine, the important things to know are how many teeth are on the crank trigger and if the engine is from a Corvette (Y-body), Camaro/Firebird (F-body), GTO, or truck. You are going to need that basic information to pick pulleys, the oil pan, and a wiring harness.>>>

The reason for our fear largely stems from rumors we've heard about incompatibility and fabrication requirements related to the installation of a Gen III into a musclecar. We've also heard it can get expensive, but we've never seen a real dollar amount. That's all going to change as we do this engine swap the Car Craft way. We'll show you every dollar we're forced to spend, every mistake, and every short cut, so you can spend the good money on only the parts you need to get the engine in the car and running, then decide if you want to go for that new blower.

The oil pan from the GTO had a front sump that crashed into the crossmember on the El Camino. We've heard that a stock full-size truck/SUV pan will fit this application but hangs really low. If you score a Camaro/Firebird engine, the pan can be modified to work on your Chevelle or El Camino by Street and Performance (S&P) in Mena, Arkansas, for about $265 exchange. In the photo, the upper pan is from the GTO and the lower pan is the modified one from S&P. Note that the GTO relocates the filter to the front sump (on the left) and the modified F-pan does not. The F-body pan also has an oil-cooler bypass fitting (lower right) that can be tapped for a manual oil-pressure gauge.>>>

On the left is the pickup supplied by S&P to reach the rear sump. The GTO front-sump pickup is still attached to the engine.

The GTO pan has an integrated dipstick and the F-body pan does not. To fit one, we simply knocked out the plug with a punch.

The upside to the modified F-body pan is that you get to reuse the factory hardware, gasket, and oil-filter position but not the original windage tray. Aftermarket companies like Milodon sell a pan that uses a windage tray and a remote oil filter.

The victim is a '64 El Camino we picked up for $2,000, with some real Midwestern rust and truck-like fatigue that guarantees we're giving you the real deal, not some cherry with squeaky-clean floorpans we picked up in Arizona or California. It is a 283/Powerglide car with a 10-bolt differential and dents and problems everywhere. We chose it to prove that you can still find a '60s El Camino any day of the week, and aside from the bed and frame, they are the same as any '60s Chevelle in terms of bolt-ons and engine fitment. And since it is a Chevy, the parts we add will likely work on your early Camaro, C10 truck, and maybe even your Nova. Later, as we add performance goodies, the things we learn will apply to your '98-and-later Camaro, Silverado, Corvette, and anything else with one of these powerplants. Interested? Read on.