Gen IV Small-Block Build - Budget LS Buildup

The new ported oil pump slipped into place and was torqued down to 18 lb-ft.

With the heads installed, it's easy to see the cavernous intake ports that can flow up to about 320 cfm into the 68cc chambers. Valves measure 2.165 inches and 1.600 inches. They'll support up to 600 horsepower with the right intake, compression ratio, and camshaft combo.

Small part, crucial role: This rear barbell oil deflector-installed with the O-ring toward the rear of the engine-is vitally important. Without it, oil will not flow properly through the oil filter.

Because the engine was designed to run below 6,800 rpm, stock pushrods were employed. Stock rocker arms were used, too. They can take up to 0.600-inch lift-within the range of even the Showroom Stock cam-as long as their correctly matched supporting components are used, too. The intake rocker arms are offset to clear the intake port.

The LS engines have coolant crossover passages between the heads, in the front and rear, to reduce air lock. We made snazzylooking crossover tubes from braided line, giving the engine a decidedly high-performance look.

These new raised-script valve covers from GM Performance Parts look great (we painted the script and Bow Tie red), but they'd lose some of their visual impact with breathers and ignition coil packs. We fixed that with some creative craftsmanship.

A special valley cover tray was made of aluminum and used to house the PCV valve in the rear and a conventional breather at the front. For the PCV valve, a hole was drilled in the tray and a baffle was welded to the bottom. Then the back of the intake was drilled and tapped for a 1.8-inch pipe; a short piece of bent 5.16-inch brake line and rubber hose completed the fabrication.

Aspiration occurs via GM's new intake manifold for the L92 heads and an optimized 750-cfm Holley carburetor.

At the bottom of the engine, an F-car windage tray, oil pickup tube/screen, and oil pan were used. Here the windage tray and pickup tube are installed.

Here's the Camaro oil pan being cinched down as the engine assembly nears completion.

Dyno tests netted a 471-horsepower/417 lb-ft best with the Hot Cam, which got the nod as the perfect street cam. It has a great sound and delivers a wide, wide powerband. The Showroom Stock cam made a lot of power, but requires an optimized setup of compression, gears, and more to be civilized.

After testing the Hot Cam, the higherlift, longer-duration Showroom Stock camshaft was inserted and the engine retuned. With the new cam, the engine picked up approximately 35 horsepower, with peak power numbers at 506 horsepower and 437 lb-ft of torque.