Project Chevelle: G-Comp Chassis Swap

Project Chevelle is back! Actually, it never left. It’s just been leading a charmed life of sitting in the shop waiting to run an errand or for a therapeutic blast around town. But about a year ago, things got interesting. Before we get into its rebirth as a G-Comp equipped Pro Touring machine, let’s recap how we got here.

Project Chevelle came to us as a one-owner, creampuff ’72 Chevelle Malibu. It was still rocking its original 307, three-on-the-tree Saginaw, four-wheel drums, and no power steering. A crew was assembled to bring the old A-body into the new millennium with some bolt-ons that would make the car more fun to drive without spoiling the retro vibe. Tubular control arms, coilovers, and four-wheel disc brakes made a huge difference. The 307 gave way to a BluePrint 383 and later an LQ9 6.0 LS. Both were backed up with a Tremec 5-speed that sent the power back to a Speedway Motors 9-inch housing and third member.

In this configuration, Project Chevelle made a couple long road trips including Hot Rod Power Tour and a few traction-challenged low-13 second passes down the dragstrip. It was a great car that was comfortable out on the road and significantly more planted through the twisties than the original suspension would have allowed for. But there’s always room for improvement, and over the past year we made some major improvements.
 

A-body Chassis Swap

 
It was a quiet morning in the Speedway Motors shop when the engineering team paid a surprise visit and stated that they needed a car to verify the new G-Comp 68-72 A-body Chassis that was in development. All eyes turned to Project Chevelle sitting quietly in the corner and a plan came together. Not only would our Chevelle serve as a mock-up mule, but we would actually build the car on the trick new chassis. The opportunity to turn the dial up even more on our Chevelle’s handling capability, not to mention slamming the stance for a more aggressive look, was all the motivation needed to tear apart a perfectly good, running car. We set a goal to have the car completed by SEMA 2026 and got to work.
 

LS Engine Refresh

 
The Escalade-sourced LQ9 6.0 in the car was plenty stout, having just a few thousand miles on a rebuild by Speedway Motors Racing Engines that made 500 horsepower at the crank. The only thing the existing engine was lacking was a little soul. The car maintained almost all of its early 70’s funk, right down to the AM radio and vinyl top. But under the hood it looked a little too generic, like someone threw some aftermarket parts at the LS to make it run with little concern for how it looked. Since the car was going to be under the lights at SEMA, something a little more unique was in order. How to make an early-2000’s engine look like it belonged in a 70’s corner-carving street racer? First order of business was to attack it with some Chevy Orange paint. That part was easy. Then we dug into our bag of tricks for a few things that might make the new-age engine look more at home within the vintage sheet metal. A cool, finned valley cover was added. LS to SBC valve cover adapters would allow for some old-school valve covers that would also hide the coils. We made some custom plug wires using the iconic Accel “Super Stock” plug wires that were a must on any hopped-up muscle car in the 70’s. Then, we hit up a friend who also happens to be a CAD and 3D printing wizard for some custom “valve covers” inspired by the old Mickey Thompson design but modified to represent Speedway Motors. Same for the intake. That finned top is a printed lid over the original FiTech manifold. Inspired by the design of the Rochester Fuelie, the intake now reps the company and the iconic 4x race cars of “Speedy” Bill Smith.

G-Comp A-Body Chassis

 
The Speedway Motors G-Comp line was designed to make old cars handle like modern supercars. That’s a tall order, but we’ve seen our G-Comp equipped test mules outrun new Corvettes at the track. Updated geometry, rack-and-pinion steering, coilovers, torque arm rear suspension and floating axles give G-Comp the chops to deliver the promised performance. On this G-Comp A-Body Chassis, the designed ride height is also way lower than a stock Chevelle, which not only helps it perform but also makes it look absolutely killer. When we rolled our freshly mocked up Chevelle outside we couldn’t believe how mean it looked. More inspiration to keep cranking toward our SEMA deadline.

With the chassis freshly powdercoated, the updated engine and Tremec transmission dropped in, and the body dropped back on, it was time to round out our chassis updates with a supporting cast to match the car’s new capabilities. A new TwoLane™ 68-72 GM A-Body EFI Fuel Tank was a perfect fit between the G-Comp rails. Up front, a new WindChill® 68-72 GM A Body LS Aluminum 3-Row Radiator dropped right in to cool the 6.0. Inside, the stock bench seat wasn’t going to cut it, so some So-Cal Bucket Seats from TMI were dropped in along with a cover to make the rear bench match. Some NVU gauges were added to look a little racier and help us keep tabs on the engine when driving in anger. Other than the lowered stance, the biggest indicators that something interesting is afoot are the big Wilwoods visible through the 18” ET LT-III Minilite wheels. 275/35-18 front and 285/40-18 rubber fills the wheelwells with no rubbing or drama.

After the usual pre-SEMA thrash, the car drove around the parking lot at 3am the night before it went into the trailer. First impressions? This thing is going to be a monster. Even one short moonlit blast revealed an infinitely better car. We can’t wait to hit the street and eventually the track to fully enjoy the latest iteration of Project Chevelle.
 
To see more on the parts used in this latest update, check out the Build List.