LSX Engine Build - The Future Of Chevy Performance Is Here

The Inside Story On How GMPP Built The World's First LSX-Based Engine

Dr Jamie Meyer May 4, 2007 0 Comment(s)
Sucp_0705_04_z LSX_engine_build The_professor_and_mr_october 2/19

The Lunati crankshaft has already been dropped into position, and Jackson is bolting down the 6-bolt mains with ARP fasteners. Notice that "The Professor" keeps an eye on "Mr. October" to make sure he takes very good care of the very first LSX Bow Tie block.

The concept of teaming up with Reggie Jackson to build a SEMA vehicle initiated in May 2006. GM Performance Parts was looking for a '69 Camaro to showcase an engine built from its new block. The Camaro would be given an "evolution" treatment: modern suspension and brakes, updated interior, paint code from the amazingly successful '09 Concept Camaro, and styling touches that matched its owner's personality and taste. We'll let you decide how the final car turned out (see the preceding story), but the engine had to match those same goals.

Once Reggie agreed to let GM Performance Parts "borrow" a '69 Camaro from his collection, the GM Design Center and GM Performance Division teams went to work, while GM Performance parts started drafting what would become the first ever application for their new LSX Bow Tie block.

Reggie loves big-blocks, as one can tell by the collections of cars that surround him. Every first generation Camaro that he owns either says COPO, ZL1, Yenko, Motion, or simply "427" on the side of it. It was clear that the LSX engine would have to exude the same qualities that the '60s big-block musclecars had. In other words, torque was going to be the name of the game with this promising small-block effort.

Sucp_0705_05_z LSX_engine_build Piston_installation 3/19

Jackson flips the LSX block over for installation of the Lunati rods and Mahle pistons.

GM Performance Parts Marketing Specialist Thomas Bates was assigned with the task of designing the LSX-based engine for the Reggie Jackson '69 Camaro. And, with the build climaxing in a test session for Hot Rod TV at GM's Milford Proving Grounds, this was going to be a car that was going to be driven with passion, not just rolled onto the SEMA show floor. Focusing on offering enhanced low-end torque with high-rpm potential, the LS family of engines is a natural for this application.

With the LSX block as the foundation, Bates whipped up a 4.185-inch bore and 4.125-inch stroke combination for nice Chevy-sounding 454 inches. Again, that's from a small-block. The rotating assembly consists of a forged Lunati crank with 6-inch Lunati forged steel rods and reverse-domed Mahle pistons for a pump-gas friendly 11.0:1 compression.

The custom Crane cam specs out at 236 @ .050 on the intake and 246 @ .050 on the exhaust with .630-inch lift on the intake and exhaust with a 110-degree lobe separation. Working with stock LS7 roller rockers (1.8:1) ratio, titanium LS7 intake valves (2.200-inch) and sodium-filled exhaust valves (1.61-inch), the LSX prototype heads flow 360 cfm on the intake at .700-inch lift. Together, this high-tech valvetrain helped the LSX 454 obtain an easy 7000-rpm red line.

Supporting equipment comes from a Holley 950-cfm HP carburetor, Stainless Works 1 3/4-inch headers, and a prototype MSD 6012 ignition.

Sucp_0705_06_z LSX_engine_build Camshaft_installed 4/19

The custom Crane camshaft has already been installed here. The cam cover is provided with every LSX block. The cam specs out at 236 @ .050 on the intake and 246 @ .050 on the exhaust with .630-inch lift on the intake and exhaust with a 110-degree lobe separation.

As part of the Hot Rod TV show, GM Performance Parts had invited Jackson to fly to Sugar Hills, Georgia, home of WJ Enterprises, to assemble the first LSX engine with Warren Johnson. Both Reggie and WJ had been looking forward to this day since the project began. And, although the two had never met in person until this date, they quickly became an "LSX Engine Assembly" team. For the most part, Reggie did all of the wrenching on his engine as WJ passed him parts and tools while making sure that Reggie was putting the engine together exactly as he should.

On September 12, 2006, at about 5:00 p.m., Reggie placed the Holley carburetor onto the GM Racing LS7 carbureted intake and proclaimed that the 454 LSX engine was ready for the dyno. Kurt Johnson had prepped the dyno room-an extension of his office in the family's race shop-for the small-block. It was the first time in 15 years that an engine other than a Warren Johnson 500-inch NHRA Pro Stock engine was going to spin the dyno at WJ Enterprises.

After some minor carb tuning, Kurt pulled the throttle block and the LSX Design Team celebrated with a 641hp, 610-lb-ft pull of the dyno. At only 3000 rpm, the LSX 454 was already kicking out over 520 lb-ft of torque, more than most factory big-blocks could ever muster. Reggie congratulated the team members and thanked them for the hard work.

Sucp_0705_07_z LSX_engine_build Rod_and_piston 5/19

Here's a close-up of the piston and rod combination for the 454 LSX engine. It consists of a 6.00-inch forged Lunati rod and a Mahle piston. The piston is technically called a 13cc reverse dome design that results in a final static compression ratio of 11.0:1 when combined with the prototype LSX heads.

Awaiting the finished engine was Al Oppenheiser, Mike Copeland, and the GM Performance Division back in Milford, Michigan. With only six weeks to completely restore, assemble, calibrate, and safety-check Reggie's '69 Camaro, they were anxiously awaiting the crate full of the assembled LSX engine. Once installed in the Camaro, GM Performance Parts would once again call on Reggie to test its new engine in a platform that he was very familiar with.

It almost seems too easy, doesn't it? The secret to a 600-plus horsepower small-block (with all of the manners of a stocker) lies in the advanced engineering and efficiency that GM Powertrain has designed into every LS engine. The LSX Bow Tie block just lets you take all of this to an extreme level. With an MSRP of $2,500 and a street price of around $1,900, the LSX block is a piece of equipment that you can get into now and build up over time, using the components that you have on hand-replacing them as you increase the capabilities of your combination.

GM Performance Parts has enjoyed so much success with the Reggie Jackson '69 Camaro, and the LSX 454 crate engine in it, that it is planning on offering the LSX 454 as a stand alone crate engine in late 2007. Of course, there are also plans to expand into an entire crate engine portfolio based on this block. As for the LSX Bow Tie block itself, it goes on sale nationwide on March 31 this year.


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