With all the data available from the sensors, and the ability of the computer to make the necessary adjustments in the blink of an eye, electronic engine management systems are what make clean-running engines that crank out 430 horsepower possible.

Throttle By Wire
The LS1 is the first passenger car engine from General Motors equipped with electronic throttle control and a version of that is used in the E-ROD system. Throttle by wire has three main components: a sensor on the throttle pedal, an electronic activator on the throttle body; and of course a control module that may or may not be part of the engine management system.

While throttle by wire seems complicated it does make it easier for engineers to incorporate other features such as cruise and traction control.

Evaporative Emissions Control
Since 1971 (1970 in California), all U.S. vehicles have had fuel systems that do not vent directly to the atmosphere. Fuel tanks and carburetors (on cars so equipped) have vent lines that connect to a canister containing activated carbon where any vapors released are trapped. When the engine starts any vapor that has accumulated is drawn into the engine and burned. When the engine is running, fresh air is drawn into the fuel tank to replace the fuel consumed.

The Future of the Hobby
At one time, building a smog-legal, modified truck was the furthest thing from most of our minds, but then who would have guessed we'd be building reproduction versions of some of our favorite designs on a brand-new chassis? It could be that the E-ROD system will be what it takes to get a new/old truck going down the road with the blessings of your state's DMV. It may also be the most effective way to meet emissions standards when swapping engines in trucks that have to get a yearly stamp of approval from the smog cops. Then again, this just may be the best way yet to have the latest in butt-kickin' horsepower that's reliable, gets great gas mileage, and is good for the environment to boot.

The Alphabet Soup of LS Engines
General Motors' LS engines can be broken down into two series: Generation III and Generation IV. They share many of the same features and attributes. Gen III blocks were made from cast iron in 4.8L, 5.3L, and 6.0L sizes (used primarily in trucks) and aluminum for 5.3L, 5.7L, and 6.0L. Gen IVs are basically the big-bore versions of the LS series and were designed to accept GM's "displacement on demand," or DOD, technology.

The first engine in the Gen III series was the LS1, which featured a bore of 3.897 inches and a stroke of 3.662 inches, resulting in a displacement of 345.69 cubic inches, however, Chevrolet called it a 350, or a 5.7L engine. Based on an aluminum block that weighed a mere 107 pounds, thanks to the deep skirt design and six-bolt main caps, it was every bit as rigid as its 160-pound cast-iron predecessor. Also found inside the block were cast-iron liners; a new, shorter nodular iron crankshaft; and powdered metal rods, the strongest to find their way inside a production GM engine.

The architecture of the LS1 block is considerably different to those familiar with the traditional small-block Chevy, there are significant differences in the heads as well. One of the most obvious is that all the intake ports are identical, as are the exhausts, which simply means that all cylinders breathe equally well. Less obvious differences in the new heads are the valve angles. It's generally agreed that the shallower the valve angles the better. The LS1 valves are at a 15-degree angle, considerably less than the earlier small-block's 23 degrees. But one of the LS head's most important attributes is the location of the fuel injectors. As these heads were designed for fuel injection rather than retrofit with it, the injector's fuel streams are aimed directly at the back of the intake valves.