Ringbrothers unveil 1,246-horsepower 1987 Buick Grand National “INVADR”

Custom build features twin-turbocharged
3.8-liter Duttweiler Performance V6

(November 7, 2024) SPRING GREEN, Wis. —  Ringbrothers, the custom car builder and parts manufacturer, has unveiled its latest creation, a custom-built 1987 Buick Grand National known as “INVADR.” The twin-turbocharged Buick produces 1,246 horsepower and 1,000 foot-pounds of torque to the rear wheels and was engineered from the ground up.

It is expected to shatter performance expectations, deliver an unparalleled driving experience and embody the singular workmanship that defines Ringbrothers.
 

Ringbrothers invested 5,000 hours to take Buick’s legendary G-body to new heights. The Grand National retains its signature angular design but has added touches that subtly highlight the extensive customization. Originally plastic, both the front and rear bumpers were fabricated from stainless steel and feature machined aluminum bumper guards.

The angle of the front fenders has been adjusted slightly and now seamlessly integrates with the new bumpers, while the rocker panels have been extended, furthering the integrated look. The factory hood was retained, but a Ringbrothers-designed carbon-fiber scoop was crafted to assist with heat extraction and enhance the design aesthetic. Covering the body is a custom BASF Glasurit Waterborne mix, fittingly called “Dark Vader Gray.”
 


“This car is all about presence. The bodywork is subtle at a glance, but the ferocity of what’s under the hood begins to materialize on second viewing. And then you drive it,” said Ringbrothers co-owner Mike Ring. “The acceleration of this car is nothing short of violent. This may well be the fastest car we’ve built to date.”


The Grand National’s centerpiece is its engine. Built by Duttweiler Performance, the 3.8-liter V6 is capable of producing up to 2,000 horsepower at 50 pounds of boost. For the current tune and daily driving, the twin Precision 62mm turbochargers produce 32 pounds of boost for a still potent 1,246 horsepower on E85. The all-aluminum engine block features six-bolt mains, custom hand-ported aluminum cylinder heads, a billet crankshaft from Bryant Racing and a bespoke intake manifold.

Channeling that power to the tarmac is a Bowler TREMEC T-56 Magnum six-speed manual transmission mated to a carbon-fiber drag-race shaft.
 


INVADR’s drivetrain sits on a custom Roadster Shop chassis and four-link rear suspension with Penske three-way adjustable shocks at all four corners, ensuring handling and ride comfort. Tamingthe ferocious power are Brembo brakes with six-piston calipers clamping down on 394x36mm carbon-ceramic rotors. The brakes are tucked behind a set of 19x10.5-inch and 20x13-inch three-piece 528-series wheels from HRE wrapped in Michelin Pilot Sport Cup 2 tires. Additionally, the underside features an integrated nitrogen-powered air-jack system that raises the car 15.1 inches, enabling quick tire changes.



The custom interior showcases uncompromised attention to detail while maintaining period-correct design cues. The team at Upholstery Unlimited hand-fabricated the seats, dashboard and center console, while Dakota Digital provided custom instrumentation. Reconfigured floor pans enhance interior comfort, and a Ringbrothers carbon-fiber steering wheel complements the balance of power and craftsmanship.



“INVADR is one of those cars we’ll remember building for a long time,” added Ringbrothers co-owner Jim Ring. “It’s a combination of state-of-the-art fabrication and imagination plus the Grand National’s DNA, culminating in an incredible final product. None of this would have been possible without our partners Gentex, HRE Wheels, BASF, Dynamat and more. We are grateful for their continued collaboration with our team.”