Other Modifications:

Crankshaft: Forged 4340 steel
Connecting Rods: Forged 4340 steel, H-beam style, Shot peened
Pistons: Forged aluminum, Full floating wrist pin
Piston Rings: Plasma-moly rings
Camshaft: Hydraulic roller, Valve lift: 632” l, 632” E, Duration @ .050” 254°l, 264° E
Lifters: Hydraulic roller tappet
Intake Valves: 2.25” Stainless steel
Exhaust Valves: 1.88” Stainless steel
Valve Springs: Dual valve spring, 1.540” coil diameter, 1.800” installed height, 197 Lbs. seat pressure
Spring Retainers: Hardened chromemoly steel
Rocker Arms: Aluminum roller rockers 1.7:1 ratio
Push Rods: High performance one piece
Intake Manifold: New! Aluminum tall deck single plane 4150 series carburetor
Rear Main Seal: New! One piece design
Windage Tray: New! Screened and louvered
Damper: High RPM torsional damper
Distributor: H.E.I
Spark Plugs: R42XLS


Jay Leno uses GM Performance Parts to Rebuild His First Love:

Everyone remembers their very first love. For many, it means a special car or truck. Rekindling the passion stimulated by a great street cruiser has inspired thousands to reclaim their past by restoring their first love. That's what happened when Jay Leno decided to rebuild and improve his vintage 1955 Buick Roadmaster.

He and Big Dog Garage shop manager, Bernard Juchli, turned to GM Performance Parts for the powertrain, suspension and braking components needed for the job. The result: a completely stock looking 1955 Buick Roadmaster that has the power, performance and handling characteristics of a serious street rod.

Leno purchased the Roadmaster in 1972 for $350 and had it restored in 1973. Jay drove it everywhere in the '70s. In fact, it was the car that he used on his first date with his wife. It also provided him a lift to his first Tonight Show appearance in 1977.

"It's special to me because it was my first vehicle here in California and it was with me during a number of other important 'firsts'," said Leno of his newly restored street rod. "Now its better than new because we've brought it into the 21st century. That means better performance, better mileage and better emissions."

Leno, an auto enthusiast and collector for most of his life, decided to restore the Buick - the first vehicle in his extensive automobile collection - and charged his Big Dog Garage crew to "bring it back to life." The vehicle, which sat in his mother-in-law's driveway for the better part of 16 years, could barely run and needed a lot of work when they started the project in 2002.

"I felt guilty that it was in such bad shape. It's kind of like falling behind on your child support. It needed more than just a restoration. It had to be better than new," said Leno.

Spoiled by the superior look and performance of his Corvette Z06, Leno decided that his cherished Buick needed some serious attention. Beginning with the exterior, the Buick received the latest classic black and silver DuPont paint, as well as new chrome. He also had wider, stock looking wheels made to accommodate wider tires. To keep the stock appearance of the wheels, Leno even remade the vintage Buick hubcaps slightly larger in order to cover the larger wheels.

The interior of the Roadmaster also received a great deal of attention, getting a complete upholstery restoration. Underneath the vehicle, the technicians at the Big Dog Garage enhanced the performance of the Roadmaster by beefing up the suspension and brake systems with Corvette C4 and C5 components.

But what makes the Roadmaster "go" was at the heart of this project. "The look of the vehicle had to be stock, but it had to be fun to drive...and I like power," Leno said. "When I heard about the GM Performance Parts ZZ572 crate engine--and the 620 horses under the hood--I knew that's what I wanted."

Juchli, who worked on the project from start to finish, agreed that the GM Performance Parts engine really made the vehicle come alive. Since he was doing most of the work on this vehicle, he also had a stake in handling the sometimes difficult engine installation process.

"The GM Performance Parts ZZ572 crate engine was the perfect solution," said Juchli. "The vehicle required some modification because it's a '55. But the ZZ572 made the job easier because it comes completely assembled out of the crate and it was easy to bolt in."

Leno says that his story is a lesson to anyone who owns an old GM vehicle parked somewhere "out back." Don't let it go. Don't junk it. Restore and improve it.

"If I had to rebuild the original Dynaflow transmission and the engine by going her or there for parts, I could do it - but eventually something usually goes wrong," said Leno. "With this crate engine, you just bolt it in, get great performance and its backed by General Motors - what's not to love?"

Jay says that his prized Roadmaster is not only the first in his extensive collection, but it is his favorite to drive. "You gotta love the look in the eyes of a guy driving a Porsche who sees you coming up on him, but just can't seem to shake you going up a canyon," he says, "He's thinking 'how can this old Buick do this to me?'"

He smiles as he tells the story, cranks up the 620 horses under the hood of his beloved Roadmaster, and goes for another drive.

About the ZZ572 / 620 Crate Engine:
The ZZ572/620 is filled with a forged 4340 steel crank with a 4.375 inch stroke; shot peened, forged 4340 H-beam rods, and forged aluminum pistons with full floating wrist pins. A new GM single plane intake manifold and 850 CFM Demon carburetor deliver enough air and fuel to reach 620 horsepower at 5500 RPM, and 650 ft. lb. of torque at 4500 RPM. And, because of the redesigned rectangular port aluminum cylinder heads, all of this power and performance is delivered with a gas pump friendly 9.6 to 1 compression ratio.

Story by General Motors Edited by Maximum-Cars.com