GM Performance Parts LSX 454 Engine - Generation LSX

The hot rod industry has been built around the small-block Chevy. After five decades of production car development, million of dollars in engineering, and countless racing exploits, GM Powertrain released the LS1. We first learned about the virtues of the LS1 when it appeared in the '97 Corvette. It took the pushrod V-8, mixed in all the tricks learned on the racetrack, and provided bulletproof performance to the masses. The LS platform quickly became standard equipment in the F-body ponycars, millions of truck and SUVs, as well as anything else with a V-8 in the General's lineup.

In loose terms, the LS architecture offers up a six-bolt main cap design in an aluminum block (in most cases), incredibly high-flowing production cylinder heads, and a deliciously quick-revving valvetrain. The LS engines are light, take up a modest amount of space, and bring race car technology to the street. It's no wonder that an entire industry has been built around LS engine/vehicle modification.

Because of the virtues that GM has built into the basic design, it's quite clear that the heir apparent to the hot rod throne is the LS small-block V-8. Irrespective of that status, the evil geniuses at GM Performance Parts have been working overtime to take the LS platform to levels of performance that no one had imagined possible. Let's take a deeper look ...

The LSX Block
We first started hearing about the "LSX" in 2006 as GM Performance Parts prepared to debut a new high-performance LS block at that year's SEMA show. GM trademarked the term "LSX," and in doing so, targeted a whole new line of parts based on the LS engine architecture. Logically, the engineers started with the foundation of any engine: the block. The GM Performance Parts LSX Bowtie Block (PN 19166454) takes the learnings of several GM divisions, and pours them into one effort that offers racers and serious street car enthusiasts the LS foundation for anything you could dream up. Its six-bolt mains, true priority main oiling system, six-bolt-per-cylinder head design, thickened deck surfaces, high-quality materials, and 4.250-inch bore capacity allow you to build up a 500-inch LS small-block (with the 9.7-inch tall deck version).

At SEMA, GM rolled out a '69 Camaro with heavy influences from muscle car collector and baseball hall-of-famer Reggie Jackson. While the car was a great example of state-of-the-art hot rodding, we were impressed with the engine. It utilized the very first LSX block, along with the engine-building skills of Warren Johnson, to showcase a 454-cubic-inch engine that made over 650 horsepower on pump gas. The Camaro ran 10.80s in the quarter-mile while hurtling the car past 140 mph on the GM Milford Proving Grounds.

With all of that experimental research and testing done for one car (and really one individual block), it was only a matter of time before GM rolled out an entire engine based on the LSX block. GM Performance Parts has always lead the industry with crate engine solutions, but the LS (and now the LSX) architecture has allowed their engineers to do something truly special.

LSX Components From GM
A whole new line of LSX parts are on the way from GM Performance Parts, and the LSX 454 is the first example of this amazing new portfolio. While it may have been two years since we first learned about the LSX block, the GMPP engineers have been very busy designing, engineering, validating, and building the pieces necessary to crank out some amazing new crate engines.

The most obvious question when you start studying the LSX block is, "What heads do you put on that thing?" After all, with six bolts per cylinder, there must be a head designed to take advantage of that additional feature. The answer is the new GM Performance Parts LSX-LS7 head--the first in a series of LSX heads coming from GM Performance Parts. While the LSX block will accept any LS-style cylinder head, the GM engineers took the already amazing LS7 head, beefed it up in key areas (valvespring perches, deck thickness, port walls, etc.) to take more abuse, and added the two additional fasteners per cylinder. The heads themselves are cast from 356-T6 aluminum and feature a ?-inch deck. That thick deck surface not only ensures a good gasket seal, but it also allows engine builders to develop their own custom combination of combustion chamber size and valve angle.

As installed in the LSX 454, the LSX-LS7 head is a study of pure efficiency. Flowing over 370 cfm on the intake--with the potential for a lot more if the end user so chooses--this head allows the LSX crate engine to feed 454 hungry cubic inches past the 6,500-rpm range. The LSX-LS7 head comes with 2.20-inch intake and 1.61-inch exhaust valves. The heads will work with either the newly released LSX-LS7 carbureted (PN 19166948) or LS7 (PN 12568976) intake manifolds. At launch time, the LSX 454 ships with the new LSX-LS7 intake and a carburetor (final selection was not defined at the time of this writing), and a fuel-injected version with the LS7 intake manifold is to follow.

The GMPP engineers didn't stop there. A complete new line of valvetrain components is also on the way. While GMPP has always had a good selection of cams, valvesprings, and cam kits, the new LSX camshaft as installed in the LSX 454 only hints at what's on the way. It's a "straight" design, with both intake and exhaust lifts measuring .635 inches, with 236 degrees intake/246 degrees exhaust duration (at .050-inch lift).

Those 454 inches come from an entirely new line of LSX engine components from GM Performance Parts. A forged steel crank (4.185-inch bore by 4.125-inch stroke) works with forged rods and 11:1 forged pistons to fill out the LSX block. These are all-new pieces designed from the ground up to deliver power and performance past what the production level of equipment allows. And, as GM's LSX trademark has come to signify, when you see "LSX" on a GM Performance Parts product, it represents only the finest materials, validation levels that only GM can reach, and horsepower potentials we've only dreamed about with such durability levels. It's an exciting time for GM fanatics and LS junkies alike.

Validation
It's hard to imagine the testing that a GM Performance Parts engine or engine component goes through. We won't spend much time going into all the gory details, but with a GM logo on the part, it gets thrashed to the limit before it goes public. GMPP has this insane validation study where an engine is kept at full load (a cycling of full throttle between peak horsepower and peak torque) for 50 hours. That's the equivalent of running 16,000 11-second dragstrip passes. It's for this reason that GMPP can easily back all of their stuff with a 2-year/50,000-mile warranty.

First Of Many LSX Crates
GMPP has got a killer new crate engine, and we'll see a bunch of new LSX parts coming out, but the real story is how nicely all of these components have been engineered to work together. The LSX 454 and its sibling, the LSX 376 (see sidebar, p. 76), are great examples of what this portfolio is going to be like. We are on the verge of having to completely readjust what we think of as "a lot of horsepower." After all, a small-block Chevy can only go so far before you start getting idle, starting, or fuel efficiency issues. These new LS engines--with a little nudge from the engineers at GM Performance Parts--are giving us levels of performance and efficiency that are hard to compare.

What's it like to drive a car with an LSX 454 under the hood? We've had the opportunity to sample both the Reggie Jackson Camaro as well as a '96 Impala and a '02 Trans Am, all outfitted with this exciting new bullet. With anything that packs over 600 horsepower, you expect a lot, and the LSX 454 delivers. Of course, with 454 cubes, it's loaded with torque. In fact, it starts making over 450 lb-ft as early as 4,500 rpm, and never has less than 500 lb-ft until you shift it. In many ways, and LSX 454 feels like a big-block, but it revs like a freight train, pulling strong past the GMPP rated 6,500-rpm redline. As for the vehicles, the Reggie car had a stick, and it was a real handful at the top end of each gear. The other two cars had various automatics (themselves part of a new line of high-performance automatics on the way from GMPP). Of the two, the Impala was a straight-out tire fryer due to a closer match of the torque converter. That car--all 4,800 pounds of it--was reported by GMPP to run in the high 11s. As for the Trans Am, it went on the '07 Hot Rod Power Tour knocking down over 25 mpg.

Conclusion
The LSX 454 crate engine will be available in the first quarter of 2009 through any GM Performance Parts dealer. You can find your closest dealer by visiting www.GMPerformanceParts.com. This engine will sell for between $12,000 and $14,000--an absolute bargain for over 600 horsepower on pump gas, with a warranty to boot. What we love about the LSX 454 is that GMPP has taken an already incredible factory architecture and enhanced it specifically for our market. If the LSX 454 is the first crate engine in the LSX lineup, we can't wait to see what they roll out next!

LSX 376: Little LSX Brother
If you want in on the LSX lifestyle, but you think the LSX 454 is just too much for you, check out the entry level LSX 376 crate engine from GM Performance Parts. This engine ships as a long-block, so you get to choose if you want to run the LS3 fuelie intake, or a GMPP LSX carbed intake. For around $7,000, you get the bombproof LSX block, a 376-inch rotating assembly, newly designed forged 10.7:1 LSX pistons, and the production LS3 cylinder heads. The engine ships with a Corvette/Camaro-spec .551-inch lift LS3 camshaft. With a production LS3 intake manifold, the LSX 376 is rated at 450 horsepower.

Of course, with the LS3 intake and stock LS3 camshaft, the GM Performance Parts LS controller and harness kit (specific for the LS3) would run this engine. We think this is a great starting point for several street car projects. This engine is begging for a camshaft upgrade, or slip a roots-style blower on the long-block, and away you go. Big cam, nitrous, blower--this things looks like it's ready to take a beating!

By The Numbers