In the 11 years since the LS-series of small-block Chevys was introduced, they have been factory-installed in everything from Corvettes to passenger cars, trucks and SUVs. It's the latter that we want to focus our attention on in this article.
Among the advantages of these engines are factory aluminum heads, lightweight composite intakes and in some cases aluminum blocks. Many, such as the 5.3L (RPO LM7) have a cast-iron block with aluminum heads and composite intake. While the LS1 has received tons of attention, the 5.3L V-8 is of a lesser-known quantity. Literally millions of these cast-iron 5.3s have seen service in vehicles like Suburbans and Silverados.
Take a walk through any salvage yard and you're bound to come across plenty that have met an untimely end. We recently did just that, visiting Dave's Golden West Auto Wrecking in Westminster, California, where we found tons of wrecked late-model Chevrolets with 5.3-liter engines.
Since the engine came out of a salvaged Suburban, we had no idea when the last oil change
For all practical purposes, the Gen III 5.3 is nearly equal to its older brother, the 5.7 LS1. In fact, the iron-block 5.3 can be bored out to 5.7, and any performance mod done to an LS1 can be done to the smaller 5.3. But that's not the purpose of this article. The goal here is to take a salvaged engine that is in good shape and add a few items to open up its nostrils so it can breath a bit easier. We were curious to see what kind of power it would make in stock trim and then with aftermarket goodies-in this instance, heads and a cam.
Most of us will never stop driving our beautiful classic cars, regardless of the price of fuel, and the modern 5.3 presents an excellent way to consume less gasoline and have excellent power for our classic rides. This particular engine will end up between the rails of a '58 Chevrolet Apache Fleetside truck.
Westech manager Steve Brule is setting up the Painless harness system we employed (more on that in a moment) and plug wires. The 5.3 came with the entire factory accessory drive system, OE harness and electronic control module (computer). The accessory drive system was removed and a Meziere electric water pump was installed. A set of long tube dyno headers carried away the exhaust. Other than that, this engine is stock.