Lock your doors. A lynch mob of angry purists is about to descend on Las Vegas. That's where you'll find a real '70 SS 454 Chevelle that's been stripped of its LS6 big-block for a Gen IV LSA small-block. Never mind that the supercharged LSA's 556 net horsepower trounces the LS6's 450 gross horsepower, this is automotive sacrilege at its best. The Chevelle's floppy chassis and factory F41 suspension are also long gone, replaced by an Ironworks custom frame and an all-aluminum C6 Corvette suspension. Nevertheless, while tossing aside the heritage and mystique of the legendary SS 454 Chevelle for not-so-legendary modern technology seems like hot rodding blasphemy, it's exactly why we like it so much.
As a magazine that espouses older classic iron over newer plastic, you'd think we'd empathize with the purists' pain. Although collectors don't go quite as bonkers for SS 454 Chevelles as they do for Hemi 'Cudas and Boss 429 Mustangs, it still ranks as one of the most intimidating and revered muscle cars of all time. We say, so what. These days, its lunch gets eaten by any ordinary six-cylinder Mustang. As far as we're concerned, if you're restoring a '70 SS Chevelle to new condition, it belongs behind glass in a museum. Some guys like Greg Heinrich "get it," and would rather drive a unique creation than park one behind a velvet rope.
We don't think car owner Greg Heinrich is worried about purists chasing him across the desert though. At 61 years of age, he isn't some punk kid who has no respect for rare Detroit iron. To the contrary, his family has been running Chevrolet dealerships for almost 50 years, so he's watched firsthand as muscle cars evolved from ordinary commuter cars to collector's items that sell for six figures at auction. Not surprisingly, Greg's a Bow Tie man to the core, having restored several midyear Corvettes, Tri-Fives, and first-gen Camaros to factory original condition. Interestingly, he's not a man who fears modern technology. He embraces it. "Some people say that they don't build cars like they used to in the good old days, and they're right. They build them even better today," Greg quips.
That same appreciation for modern technology directly influenced the destiny of his Chevelle. "When I first purchased the car 20 years ago, it was in very rough shape. It had extensive hail damage, the floors were rotted out, and the original LS6 was long gone," Greg recalls. Although he considered scrapping the project entirely and cutting his losses, some mysterious force—perhaps the purist deep within his psyche—convinced him that it was a car worth saving. After performing some extensive sheetmetal repair, Greg painted the Chevelle at his dealership. For the next 15 years, Greg made do with a GM 454 crate motor matched with a TH400 transmission, but he found the Chevelle's driving dynamics terribly unsatisfying. "I got frustrated with the car because it handled like an old '70 Chevelle. It didn't steer, brake, or ride well, and driving a black car in Las Vegas without air conditioning isn't much fun at all. I took the car over to Roger Lee at Ironworks Kustom, and told him that we need to make this thing drive like a modern performance car."
While many hot rodders would be perfectly content cruising around in a real SS 454, even if the engine isn't original, Greg admits that he's been spoiled by the virtues of modern technology. Other cars in his stable include an LS9-powered '57 Chevy and several LS-powered street rods. Obviously, Greg isn't a hot rodder who is easily impressed, but he's smitten with the power, smooth street manners, and fuel efficiency of the LS-series small-block. Having tried just about every Gen III/IV crate motor in the Chevrolet Performance catalog, he decided to go with a supercharged LSA small-block this time around, which is essentially the same 556hp beast strapped to the Camaro ZL1 from the factory. To tame the LSA on long-distancing cruises, it's mated to a Tremec T56 Magnum six-speed manual transmission, which routes the torque back to a GMR 9-inch rearend.
Ironworks built a custom instrument panel, which houses the A/C controller and air vents.
Sitting low is cool, but no one wants to scrape stuff. To eliminate the potential for drag
Stitch By Stitch Interior (Yucaipa, California) gets credit for rehabilitating the Chevell
While big horsepower numbers are always impressive, getting it to stick is much more difficult. Likewise, enhancing grip without ruining ride quality is even more challenging, especially when plans call for an extremely aggressive stance. The only logical solution to satisfying these contradicting design goals is building a new chassis from scratch, which is exactly what Ironworks Speed and Kustom (Bakersfield, California) did. The company offers turnkey frames for Chevelles, Tri-Fives, and '58-64 Impalas that boast revised suspension pickup points and optimized geometry. When matched with all-aluminum C6 Corvette front control arms and spindles, the result is vastly improved handling and a mean stance that doesn't sacrifice ride quality. In the rear is a custom Ironworks four-link that's fully adjustable to help put the power down. "Our frames are laser-cut from flat-plate steel and fully TIG-welded for strength. The frame has been designed to accommodate the lowest ride height possible with the optimum suspension geometry at that ride height," explains Roger Lee of Ironworks.
Cutting-edge chassis hardware aside, A-bodies are still heavy cars that require big patches of rubber to keep them planted to the pavement. Thanks to framerails that have been kicked inward, the Ironworks chassis swallows up fat meats with ease. At 295 mm, the Chevelle's front tires are wider than the rear tires on many Po Touring machines, and the car's 335mm-wide rear tires put down quite a large footprint as well. They wrap around Grip Equipped Laguna wheels measuring 19x10 up front and 20x12.5 out back. Stopping duties come courtesy of Wilwood 14-inch rotors clamped by six-piston calipers. Although disappointment was the original inspiration behind the Chevelle's Pro Touring transformation, Greg is now a very happy camper. "I wanted a car I could take a 500-mile road trip in and still be comfortable, and Ironworks has delivered just that. The Chevelle has a ton of power, it hooks up very well, and it idles nicely, too," Greg says.
Needless to say, it doesn't sound like Greg has any regrets over giving his car a full modern makeover. "If this car still had the original LS6 motor when I bought it, then I wouldn't have built it the way that I did. Since it didn't have the original engine anymore, I wanted to build a car that was actually enjoyable to drive," he explains. "Muscle cars were phenomenal for their day considering the technology that was available back in the '60s and '70s, however, we've come a long way since then. A 454 big-block only made 450 hp back then, but now we have small-blocks that make just as much power. As cool as muscle cars were for their time, they're even cooler when you combine them with today's technology."
Whether Greg's reasoning is enough to keep the lynch mob at bay remains to be seen. Purists are a passionate bunch, and many will insist that the proper course of action would have been building a 454 with a bunch of original date-coded parts for the sake of keeping Greg's SS 454 Chevelle as period-correct as possible. Nevertheless, it's hard to fault a hot rodder who put pragmatism ahead of sentimentality. Any purist who has a problem with that will have an awfully tough time keeping up with Greg's LSA-powered Chevelle in any muscle car built to period-correct specifications.
By The Numbers
1970 Chevelle SS
Greg Heinrich, 61 • Henderson, NV
Type: GM LSA small-block
Block: factory 4.065-inch bore aluminum
Oiling: stock pump and pan
Rotating assembly: GM 3.622-inch forged steel crank, powdered metal rods, and 9.1:1 hypereutectic pistons
Cylinder Heads: stock rectangle-port castings with 2.16/1.59-inch stainless steel valves
Camshaft: GM 198/216-at-.050 hydraulic roller with .492/.480-inch lift
Valvetrain: stock lifters, timing set, and 1.7:1 rocker arms
Induction: factory 1.9L Eaton TVS supercharger, intake manifold, and throttle body
Ignition: stock LSA
Exhaust: custom 2-inch long-tube headers, custom X-pipe, dual 2.5-inch MagnaFlow mufflers
Cooling: stock water pump, AutoRad radiator
Output: 556 hp at 6,100 rpm; 551 lb-ft at 3,800 rpm
Transmission: Tremec T56 Magnum six-speed manual, GM dual-disc clutch, Twist Machine shifter
Rear axle: GMR 9-inch rearend, 35-spline axles, 4.11:1 gears, and limited-slip differential
Front suspension: Ironworks C6 Corvette control arms, custom splined sway bar, RideTech coilovers
Rear suspension: Ironworks four-link and splined sway bar; RideTech coilovers
Brakes: Wilwood 14-inch rotors and six-piston calipers, front and rear
Wheels & Tires
Wheels: Grip Equipped Laguna 19x10, front; 20x12.5, rear
Tires: Michelin PS2 295/30R19, front; 335/30R20, rear