We recently had a chance to crawl all over a new ride to the Chevy High Performance stable, an LS-powered 1966 Chevelle SS clone, owned by our own associate publisher, John Barkley. The basics include a carbureted 6.0L LQ9 engine out of an 2005 Silverado, a TCI Automotive 4L60E Street Fighter transmission, and a 12-bolt rear with 3.55:1 gears and a Posi unit—a combination that we felt was a great build for an attainable, modern-day muscle car. Even in this initial form, which still sports stock brakes and suspension, the snappy, button-shifted overdrive trans (trans can be fully automatic or manual button shifted at the flip of a switch) combined with the power of the LS makes driving the car a tire-barking fun time. If we didn't know any better, we'd think a carbureted big-block was lurking underhood, but that's only half-right. "The engine throws people off at car shows," Barkley says, about his late-model bullet. "Some stare for a while before asking, ‘Which engine is that?' Or, ‘When did Chevy release a big-block with coil-on-plug ignition?'" The Chevy Orange paint, individual header primaries, combined with the Z28 dual snorkel air cleaner, and separated runners of the intake manifold makes the engine look like some exotic GM secret engine from the 1960s, but in fact, it's a just a common truck engine from this decade with some carefully selected performance parts that makes this piece stray from your typical GM powerplant.
Over the past year, we watched a very simple setup come together, consisting of parts from companies like Holley, TCI Automotive, MSD, Aeromotive, Edelbrock and a handful of others that we felt made up an effective formula for any tire-smoker. While the '66 is not destined for any type of motorsport in particular, it's just a cool old car with an interesting engine and some features that made even a short cruise around the block a fun time. "The goal of the project is to be a comfortable driver that can be drag raced and taken to the autocross, but it will also be a compromise among all three," Barkley says. While we do have plans to take the Chevelle to the next level with some chassis parts from Detroit Speed Engineering, some more aggressive Cragar 18-inch wheels and stickier tires, and a Strange S60 rearend, until then we're enjoying tooling around in a Chevy that feels both nostalgic and modern, simultaneously.
The Regal Red SS clone was purchased with a very tired 396 with a greasy M21 four-speed behind it, but that combo didn’t last long.
At the Source Interlink Tech Center in Irvine, California, our Tech Center manager, Jason Scudellari, began transforming the ‘66 into a highly functional muscle car with one of GM’s most venerable V-8 engines: the LQ9.
THE ENGINE AND COOLING SYSTEM
The LQ9 engine could be found in the 2002-06 Cadillac Escalade EXT and ESV, ’03-07 Chevy Silverado, SS, and a couple different optioned GMC Sierra trucks. It displaces 6.0 liters with about 10.4:1 compression. The compression ratio combined with the GM’s better cathedral-port castings, and over 360 ci, makes this a great platform for making streetable power. This particular engine made about 495 hp on the engine dyno with just an different cam (COMP Cams hydraulic roller with 228/230 at 0.050).
To help mask the engine’s origin, the 6.0-liter was fogged in the classic Chevy Orange paint from Summit Racing (PN SP-1005), including the Edelbrock intake manifold (PN 71187).
Instead of the typical composite intake and forward facing throttle body, we opted for the non-EGR Performer RPM intake so we could run a carburetor for simplicity, but we do have plans to go with a new self-learning EFI setup eventually.
The LS was fitted in the A-body frame using Energy Suspension’s conventional SBC engine mounts (PN 3-1114G). The Doug’s Headers adapter plates bolt to the LS engine and allow for a standard Energy Suspension motor mounts to be used.
We had to install an extra plate to raise the motor in order for the Holley pan to clear the crossmember. The plates can also be used to move the engine closer to the firewall with some slight modification, too.
Before bolting up the TCI Automotive trans to the motor, Scudellari made sure to install the correct TCI early trans flexplate and spacer to bolt TCI Automotive’s 10-inch converter to the flexplate. Without this piece, the hub on the back of the converter wouldn’t fit into the back LS crank correctly, and in turn, the front pump would not engage properly. For those who are wondering what’s with the special adapter, we actually ordered our 4L60E transmission with an early bolt pattern case so we have other engine options, otherwise this is a very common LQ9/4L60E combo that bolts together.
AFCO’s dual-core aluminum bolt-in radiator and dual fan kit was used for the main cooling components in this build.
Earl’s Plumbing supplied the transmission and engine oil coolers for this project and we were able to install them behind the factory slots in the bumper for directed airflow.
The black coating isn’t just aesthetically appealing, it also helps dissipate heat.
FUEL SYSTEM AND EXHAUST
Aeromotive supplied the fuel system for this build, including all-black AN-8 fittings, a bypass fuel pressure regulator (PN 13204), carburetor fuel log (PN 14201), and an A1000 fuel pump that we installed into the tank.
Scudellari installed the Tanks replacement gas tank that was modified by Rock Valley for the Aeromotive in-tank pump.
The Chevelle trunk floor needed a small box to clear the Aeromotive unit. Although we are running a carburetor on the LQ9, this fuel tank and system features a return line and fuel well for when we decide to upgrade to EFI in the future.
An Edelbrock intake manifold was used to convert the fuel-injected LQ9 to use a 750-cfm 4150-style four-barrel carb from Holley (PN 0-80508S). The fuel log from Aeromotive we chose is a versatile piece and the pivoting fuel log holds a large amount of fuel itself, making sure that the bowls are always fed.
Aeromotive’s bypass fuel pressure regulator gets screwed into the back of the fuel log and controls the pressure on the return side of the system. This piece also has an orifice for boost reference if we decide to go that route, too.
Doug’s long-tube headers were used for this project (PN D3336), which feature a ceramic coating that dissipates heat more effectively, keeping the temps under the hood down, and some say it increases power slightly.
ELECTRONICS AND IGNITION
The brain of the operation is MSD’s 6LS ignition system (PN 6010). This box simply hooks up into the factory harness with four connections and allows you to use the coil-on plug ignition in combination with the carburetor. This piece features controllable rev limits, timing adjustment, and the hot multiple sparks that come with MSD’s high-performance ignitions.
The 4L60E TCI Automotive Street Fighter transmission is controlled via this EZ-TCU (PN 302820) unit that allows the user to configure speedometer, shift points, and even allows for button-controlled shifts.
TCI Automotive’s Outlaw shifter with dual buttons (PN 611641) was also installed into the Chevelle. Scudellari was able to wire it so you can shift the car via the two buttons on the handle. Pulling the trigger on this piece at high rpm results in a neck snappy shift that effectively barks the BFGoodrich tires nicely.
This electronic, cable-controlled TPS sensor is also used in conjunction with the 6LS box and EZ-TCU and basically tells the computer where your throttle position is without having a traditional throttle body.
Inside the car, the factory dash was removed for Dakota Digital’s XLS dash, which features a tachometer, changeable colors, and all the important instruments that the factory display does not have. Look for a full install on this piece in an upcoming issue.
Here's the Dakota Digital XLS dash, installed and ready to go.
DRIVETRAIN, CHASSIS, AND ROLLERS
With the transmission and LQ9 bolted into the chassis, Barkley opted for a classic Z/28 airbox, an air-conditioning setup from Vintage Air (which positions the compressor in a higher location than the standard LS), and the factory LS serpentine system.
A Dynotech aluminum driveshaft was ordered for the Chevelle and tied our 12-bolt to the 4L60E nicely. The exhaust system is from Flowmaster’s American Thunder series, which Scudellari bolted up to Doug’s long-tube headers.
Here's a shot of the whole thing assembled.
Under the car reveals the Holley LS swap oil pan (PN 302-1) nestled over the factory K-frame. We actually had to space the engine up a little to clear the sweep of the steering centerlink.
The wheels on the Chevelle are YearOne’s 17x8 aluminum Z28 replicas, while the tires are Fuzion ZR1s that measure 245/45/17 in the front and 275/45/17 in the rear. The suspension and ride height are totally stock, but that will change.
You could call this "Stage One" of this Chevelle buildup, as plans for a full Detroit Speed & Engineering suspension upgrade, a Strange Engineering S60 rearend, self-learning fuel injection, and more aggressive wheels and tires are also in the works for this Chevelle. Keep following the magazine to find out what this car can do on the autocross, as well as the dragstrip.