Forward Into The Past

GM's LS-1 gets an old-school induction

Okay here goes--my first assignment, and I'm gonna end up showing my age. As you may surmise from my story choice, I'm no techno rodder. True, I'm a heck of lot more comfortable with a newspaper than I am with the Internet, and I'm far more comfortable with a good four-barrel than I am with electronic fuel injection. In fact, my own daily driver is powered by an early-'60s 327 with three deuces and solid lifters. That said, I am well aware of the drivability and fuel mileage benefits of you youngsters' computer-controlled, tune 'em with a laptop road-rockets, but I have to admit, the technology intimidates me. Perhaps the SUPER CHEVY staff will soon educate me enough that I'll understand it, but I think I'll be sticking to what I've overheard some members of the younger generation calling "a controlled fuel leak"--a carburetor--for a while longer.

The good news, for me (and I'm hoping for many like-minded souls) is that we're not alone! One of the most revered pioneering companies in hot-rodding history has seen fit to spend the R&D time and a chunk of cash developing and marketing intake manifolds (and needed components) to convert GM's most sophisticated and advanced small-block V-8, the Third-Gen LS1, to good ol' carburetion. Yahoo!

Now, just for those of us who've never paid much attention to GM's Third-Gen because we never intended to get involved in its complicated (to us) technology, here's a bit of background on what we've missed.

The LS1 engine first appeared in the '97 Corvette and in '98 F-bodies. Even though it represented GM's Third-Gen small-block, its design was entirely new. The LS1 is based on a four-bolt aluminum block with cross-bolt mains, a nodular cast-iron crankshaft featuring hollow main-bearing journals, forged powdered metal connecting rods, and flat-top pistons. Topping the block are a pair of 15-degree aluminum cylinder heads featuring tall and narrow symmetrical intake ports along with evenly spaced oval exhaust ports, hydraulic roller lifters, a composite intake manifold, and a new firing order to decrease engine vibration. The Third-Gen engine design also employed a distributor-less ignition system using sensors on the crankshaft and camshaft to determine top dead center in order to fire one of eight individual coil packs in the proper sequence. The distributorless ignition system also required a more advanced electronic control module (ECM) to control the spark fuel curves.

By 1999, the Third-Gen design found its way into Chevy trucks and SUVs. These vehicles used almost identical engines with the following exceptions: the engine blocks are cast-iron and use a different oil pan, the intake valves in the cylinder heads are smaller, a taller intake manifold raises the runners, and a dual fuel-line return system was used. Since the introduction of the Third-Gen engine, several different fuel systems and camshafts have been used, as well.

Today, GM offers a complete, injected LS1 in crate engine form (part number 25534322), but since they've been used since 1997, they're becoming much easier to find in boneyards and swap meets, which would be a lot more affordable for those of us with little interest in its fuel injection and electronics. The LS1 in stock form specs out at 346 ci and is rated at 320 hp at 5,800 rpm and 330 lb-ft of torque at 4,400 rpm. Its compression is 10.25:1, and it's fitted with a hydraulic roller cam with 0.500/0.500-inch lift with 119.5-degree separation. Combine this with its weight advantage over an iron block, and it's obvious that this would be a great choice for any early Chevy swap.

Okay, I can just hear it, "What! Why would anyone want to mess with that? The LS1 is a technological work of art. That'd be like taking a brand new high-performance pickup and fashioning it after a 56-year-old design--oops, wait a minute . . . All kidding aside, this is a great opportunity for those of us who'd love to slip one of those Third-Gen between the inner fenders of our early Chevy. Just think, no high-pressure pumps, fuel return lines, fuel tank swaps--and no huge complicated piles of wiring, sensors, and electronic control units!

Which brings us to the crux of the biscuit, so to speak--Edelbrock's new intakes and electronic ignition controller (manufactured by MSD) not only fit the LS1, they also fit the Corvette LS6 engine and any other Gen III engine including the LM7 (5.3-liter), LR4 (4.8-liter), and LQ4 (6.0-liter). And as I've stated, they allow the use of a carburetor on these originally computer-controlled engines, offering maximum power and a broad torque curve from 1,500 to 6,500 rpm. The Performer (also available is a Victor Jr. design) manifold made with 410 hp and 418 lb-ft of torque in dyno tests with Edelbrock's matching cam (#2215) and Performer Series carb (#1413). The Performer RPM LS1 kit includes a wiring harness and the aforementioned electronic Timing Control Module that works with OE sensors to fire the coil-on-plug ignition system, and offers a choice of three timing curves. A special throttle and trans bracket that works with 700R-4 and Turbo 350 transmissions is included, again, making the LS1 engine an easy retro-fit into any musclecar or street rod.

So enough with the song and dance; check out the accompanying images and then get on the horn with Edelbrock to see what you've been missing--then start searching the swap meets and junkyards so you can get crackin' and bring that hot rod of yours into the 21st century--even if you do it the old-school way!