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Inside the COPO Camaro Supercharged-350ci LS7 Engine

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By Miles Cook

Photos Courtesy of Chevrolet Performance and Fastest Street Car Magazine

In 1969, big-block Camaros were not generally available with a 427. The biggest hitter was the 375-horsepower 396 also known as the L-78. The L-78 could be outfitted with optional aluminum cylinder heads, which then turned it into an L-89, which today is a very rare and desirable collectable Camaro.

To get a 427 in a ’69 Camaro you had to go through the “back door,” so to speak, and order a 427 Camaro through GM’s COPO program, which is an acronym for Central Office Production Order. In 1969, there were two options for a COPO 427 Camaro. The first was COPO 9561, which meant the car came with a cast-iron 425-horsepower 427 known as the L-72. COPO 9560 was the ZL-1, which was an all-aluminum 427 “rated” at 430 horsepower, but easily made upwards of 550 with just headers and a better flowing exhaust system. Only 69 were produced now almost 50 years ago.

Forty-three years later, Chevrolet Performance created a new COPO, in the same mold and spirit as the original, as the initial Fifth-generation COPO Camaro was introduced in 2012. Since then GM has produced 69 COPO Camaros each year from 2012 to today in 2018.

The COPO 350 SC comes factory equipped with a 2.9-liter Whipple supercharger. The valve covers and ignition coils are production LS components.

Now seven years into COPO Camaro production, the current the Sixth-generation car introduced in 2016 continues the factory hot-rod tradition, with Chevrolet Performance’s limited edition, factory-produced, turnkey race car. As delivered, its LS-based, supercharged COPO 350 routinely pushes COPOs into the mid 8s.

The COPO’s many features include an ATI Turbo 400 transmission, an 8.50-certified roll cage, an adjustable coil-over front suspension, a four-link rear suspension with coil-overs and a Panhard bar. There is also a 9-inch rearend (that replaces the car’s stock independent rear suspension) with an aluminum center section that has a steel spool and 40-spline axles, lightweight disc brakes all around, a custom manual steering rack and a fuel cell with an Aeromotive fuel system and built-in Aeromotive high-pressure fuel pump. It is Chevy’s entry in the NMCA Factory Super Cars class and competes heads-up with the Cobra Jet Mustangs and Drag-Pak Challengers fielded by Ford and Dodge, respectively. And while the car is really cool, our focus here is the LS-based supercharged COPO 350 engine that now reportedly produces more than 1,000 horsepower in NMCA Factory Super Car trim. Let’s take a look.

From The Factory

Naturally, Chevrolet Performance is a major element here since they’re the ones that offer the COPO Camaro for sale to racers in the first place. We spoke with Tom Wysocki, who is the GM COPO Program Leader.

“The COPO engines are built at the Global Propulsion Systems, Pontiac, Michigan Engineering Center,” Tom told us. “One end of that facility is the Performance & Racing Center where other engine programs are also housed, including Corvette Racing where the engines for those C7R racecars are built to race at sportscar racing events such as the 24 Hours of LeMans among others.”

“Since 2012, we’ve built 69 cars a year with now one of three powertrains to NHRA tech specs for Factory Stock. The supercharged 350 is the one that competes in the NMCA Factory Super Cars class. The engines are then gone through by aftermarket entities such as Barton Racing and they add mods within rules such as a 1.9:1 ratio rockers, rocker bars, roller followers and larger-diameter lifters. Full blueprinting is also done by the engine builders that campaign the cars in NMCA’s Holley EFI Factory Super Cars. You could say we make the basic COPO package and the aftermarket takes it from there,” said Tom.

The COPO 350 SC uses a cast-iron LSX block for bulletproof strength easily supporting the 1,000-plus horsepower output of these engines. Estimates now put that number closer to 1,200.
 

What were the basic parameters of the engine build at the beginning?

“The supercharged program started in 2012 and we used the Whipple because that was what was out there (such as Cobra Jet),” said Tom. “NHRA lets all three groups of racers including Chevrolet, Ford and Dodge run the same rotor-set just packaged a little differently for each engine. The 2.9-liter Whipple was a proven commodity, so it was a good fit,” he related.

“In 2012, the first COPO engine was a 327, a 5.3-liter engine and that was the only year it was offered. It was offered with 2.9- and 4.0-liter blowers, but the 4.0-liter was put into NHRA Super Stock because of power output. After 2012, the 327 was made into a 350 and was allowed to run with the 2.9-liter blower in NHRA Stock, which was the largest-displacement engine and supercharger to run in the class,” Tom also commented.


The COPO 350 bottom end is anchored with a Callies 4340 forged-steel crank.

What determined the power durability goals and what in-house tests are done?

“The goal was to run a couple of seasons without any kind of a rebuild, be maintenance free and be able to make 200 passes. The dyno durability testing replicated at least to 200 runs including burnout and staging. The staging, quarter-mil run, and back-to-pit is pretty much an at-the-track playback. If you close your eyes while in the dyno and listen to the run, you will think you’re at the track. On the engine dyno, an rpm trace is performed by the dyno. You will hear it stage, come up on the two-step, launch, and do the 1-2 and 2-3 shifts. We used comparable durability testing from the LSX454R for the COPO program. If there are any major changes to the car, we make 50 passes for testing—real passes in the car.


Callies also supplies the forged-steel connecting rods that are fitted with ARP rod bolts.

What are the details on the individual components of the engine?

“It starts with an LSX cast-iron block equipped with steel main caps. The COPO 350 SC uses a Callies 4340 Dragonslayer crank with a double-keyed snout. There are also Callies 4340 H-beam Ultra forged-steel connecting rods in a 6.350-inch length and Mahle forged 2618 alloy pistons with a Graphal coating and friction-coated skirts. Compression is 10.9:1.

The CNC-ported LSX-LS7-based heads are ported in the Pontiac, Michigan, Racing Center with unique porting and valves for COPO. They are fitted with Del West intake and exhaust valves, which are 2.205 and 1.61 inches, respectively. Other pieces include PSI beehive valvesprings, LS7 rockers, Johnson lifters and Trend pushrods.


An ATI Super Damper with a 10-rib shell is used on the COPO 350.

The Whipple blower is home to a Whipple 109mm throttle body, and a Stefs oil pan is used. American Racing supplies the headers.

Limited to a .641-inch lift by the NHRA, the COPO 350s are fitted from Chevy Performance with a Comp Cams hydraulic roller with a 242-/257 -degree duration at 0.050-inch tappet lift.

To survive at the relatively high RPM that they often are revved to, the COPO 350s use Johnson lifters along with LS7 rocker arms and Trend pushrods.

Patterson-Elite Performance and Ray Barton Racing Engines

We also spoke with Todd Patterson at Patterson-Elite and David Barton from Ray Barton Racing. They provided a number of interesting facets about the COPO program.

Patterson-Elite provides horsepower to several NMCA and NHRA programs, including Ted Hughes’ Omaha Track 2016 COPO Camaro.

Todd Patterson—

At Patterson-Elite, we prepare and maintain two cars for Ted Hughes. One is for Factory Super Cars and the other is for CPS, which is Chevy Performance Stock. The CPS car runs an LS376 sealed crate engine and the Factory Super Cars entry uses the COPO 350. Both are sponsored by Omaha Track, which is a railroad rail-replacement company.

The deal came together last year and Ted likes the NMCA format because it’s feasible for him to make all the races. We think the NMCA does a nice job of prepping the track and making it sticky, and that helps because these cars only have a 9-inch-wide tire and that’s a considerable limitation.

Everybody keeps trying to build more power, but you can’t put a bigger tire on it. It has turned into a power-management type of class and you have to be pretty savvy in the fuel-injection department to be able to take timing out and know where to put it back in, to get the car to work in the first 30 feet or so of the track. After that and you can start ramping it back in.

The biggest challenge is the changing track conditions. A cloud-covered run compared to bright sun causes a change in track temperature of around 10-15 degrees. Some guys just light them up and sometimes the races turn into a Funny Car pedal fest sort of thing. The fastest car doesn’t always win, which puts a little twist into it. I do prefer to see two cars going down the track side-by-side and that’s what fans like to see, but one of the biggest things that’s appealing about these cars is the fact that people in the stands can relate and identify with them. They can buy a new Camaro on Monday or they may already have one. They are the same bodystyle as cars on the street. And in these stock-appearing-bodystyle Camaros, the Whipple blowers are spinning upwards 20,000 rpm and the engines are pushing close to 1,200 horsepower with 8,000-rpm capability.

One area where we have some room to make improvements is the rocker arms, which are a pedestal setup with a 1.8:1 ratio. We go with 1.9:1 arms and a shaft-rocker-arm assembly, which is also allowed as an upgrade.

Racers run both Fifth- and Sixth-gen cars. Both have varying favor among different racers. The rear suspension is the same on both cars, with their 9-inch housings and non-adjustable four-link setups.

Scott Libersher has a fleet of COPO Camaros and Ray Barton Racing Engines provides the horsepower for their NMCA Holley EFI Factory Super Car and Coan Racing Stock/Super Stock programs.

David Barton—

We have several COPO customers. As far as NMCA racers, our main guy is Scott Libersher (Click: FSC May 2018, page 54) and his son Lenny as well as son-in-law Dan Condon. They contacted me two years ago and said to me that for 2017 it was a big dream of theirs to win a championship. That is how we got involved in the NMCA side of things. And Scott had already been racing in the NMCA for a couple of years.

We put together a plan and he flies me to all the races and I get to play crew chief for the weekend, which is nice because it’s a good learning curve for me personally. I like not being the driver on occasion so I get to see things from the other side of view. We learn things at every race. I like seeing things from the other side of the fence.

In Scott’s case, I like to see him focus on his team winning races, which is good for business. It’s nice to help customers when we can make time for it and help them be successful as well. We don’t just build the motor and send them on their way. We help to run it and manage it and deal with the power management. That’s why I like going personally to each race to help people out.

We got involved in 2016 with COPO and before that we were doing the Dodge Drag Pak cars. One of our top Hemi customers, Gary Wolkowitz, wanted to buy a supercharged COPO and said he would buy one if I want to drive it. We did much of work on it as well and won several races in NHRA in 2016 and 2017. It was first time we ran a Chevy and a supercharger after doing mainly the Dodge stuff. If it wasn’t for Scott, we probably wouldn’t have been as likely to get into the NMCA racing, but we are certainly glad we did. It has opened a lot of doors for us and we appreciate that. It swings both ways as it helps us and we help them. The COPO program has turned into a good market for us with around 500 or so COPO cars produced since 2012.

Sources

Chevrolet Performance

www.chevrolet.com/performance

Patterson-Elite Performance

www.patterson-elite.com

Ray Barton Racing Engines

www.raybarton.com



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Mike Galimi
Mike Galimi is the Director of Content & Marketing at ProMedia Publishing and Events with nearly 20 years of experience in motorsport writing and photography.
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