The Six-cylinder Firebird Sprint: Slouch or sleeper?

1967 Firebird Sprint pulled plenty of power from six cylinders

Bill Krause’s 1967 Pontiac Firebird Sprint convertible is not only
a fun and nimble driver, it’s also the featured car for August in the
Old Cars Collector’s Edition 2010 Calendar.

It’s not often when a six-cylinder engine and a reputation for performance can share the same engine bay. For enthusiasts of Pontiac’s inline, overhead-cam (OHC) 230-cid six-cylinder, the question posed in the above headline is a moot point. When fitted with the Pontiac Sprint package’s Rochester Quadra-Jet carburetor, this powerplant produces 215 hp. And with the lighter weight of a six when compared to a V-8, less nose weight helps lift the performance level of a Pontiac OHC six-equipped Sprint well beyond slouch status.

One avid supporter of the Sprint six is Bill Krause, who recently restored his one-family-owned 1967 Firebird Sprint convertible. The Woodbury, Minn., resident has had a vested interest in the car since it was purchased new by his father George from the now-closed Hanford Pontiac dealership in downtown Minneapolis.

“I went with my dad when he bought the car,” Krause recalls. “We used my grandmother’s 1962 Oldsmobile as a trade-in. I still have every scrap of paper from the purchase.”

Krause readily admits, though, that when he displays his Firebird at shows and opens its hood, he gets some confused looks. “Everybody expects to see a 326 or 400 [V-8].”

Owning and restoring a car that’s been in his family for more than 40 years is a source of great pride for Krause. Rebuilding his Firebird’s original six-cylinder instead of replacing it with a more common V-8 just ups his satisfaction level.

DeLorean’s innovation

Pontiac’s OHC six-cylinder engine was the brainchild of Pontiac Motor Division executive John Z. DeLorean. Most noted for his later work with the stainless steel-bodied, gullwing-door DeLorean DMC-12 coupe that became a pop-culture icon from its starring role in the “Back to The Future” movie trilogy, DeLorean pushed to get the OHC six into a Pontiac in 1966. He wanted a a domestic car that could be marketed to compete with imported European sports cars such as Jaguar.

America’s first mass-produced overhead-cam engine, Pontiac’s OHC six was ahead of its time on several fronts. It featured a now-common reinforced rubber cam timing belt. The six’s lighter weight (when compared to a V-8) also provided better handling and steering response, which were huge marketing points when Pontiac was trying to attract devotees of imported sports cars such as Alfas, MGs and Triumphs.

It takes up less room in the engine compartment than a V-8, but
Pontiac Sprint’s OHC six-cylinder equipped with a four-barrel
carburetor offers plenty of power in its downsized package.

When the optional Sprint version was ordered, the upgrades included a high-lift/longer-duration cam, dual valve springs, a unique harmonic balancer, dual exhaust manifolds, high-flow intake manifold, 20:1 manual steering gear box, high-performance suspension and a V-8 clutch disc and pressure plate. Additional Sprint options included a four-speed manual transmission with Sprint gearing plus a 3.55 Safe-T-Track rear end.

DeLorean introduced the OHC six in both Pontiac’s Tempest and LeMans models (except station wagons) in ’66. In its original base configuration, the 9.0:1-compression engine was equipped with a Mono-Jet carburetor and rated at 165 hp. When ordered with the optional Sprint package, compression increased to 10.5:1 and a Rochester Quadra-Jet carburetor replaced the single-throat base unit. Horsepower also increased to 207. In this enhanced format, a Tempest or Lemans Sprint model was capable of running the quarter mile in mid-16 seconds at more than 80 mph.

And for those who are wondering, Marty McFly (portrayed by Michael J. Fox) needed to achieve 88 mph over a quarter-mile in his Flux Capacitor-powered DeLorean to achieve time travel in “Back to The Future.” And that was 20 years after Pontiac introduced the Sprint.

It was a natural evolution in 1967 when Pontiac launched its sporty Firebird that one of the five models offered would be a Sprint. Both Tempest and LeMans models (except wagons) also retained their Sprint option status.

Available in both soft- and hardtop versions, the OHC six-equipped Firebird could be ordered in base (Mono-Jet carb, 230-cid/165-hp) or $116.16 optional Sprint versions. For ’67, the Sprint OHC six had its horsepower rating increased from 207 to 215.

The Sprint package — which included a three-speed floor-shift manual transmission, Rochester Quadra-Jet carb, body sill moldings with “OHC-6 Sprint” emblems and F70x14 black sidewall tires — added 55 lbs. to a Firebird’s curb weight. For $14.74 more, Rally stripes could be ordered. An additional $42 would add a hood-mounted tach. A four-speed manual gearbox was also optional for $184, and when so-equipped, a Firebird Sprint could traverse the quarter mile in mid-17 seconds at 80 mph.

Pontiac legacy

Krause said his dad has always been both “a sports car guy and a Pontiac guy.” The lean towards Pontiac products all began with George Krause’s father, whose first new car was a 1934 Pontiac.

When the Firebird arrived in 1967, Krause said his dad found the sporty newcomer to be the perfect driver. The Sprint’s 215-hp OHC six was George’s desired engine for both its power-to-weight ratio and the more nimble driving feel it offered.

When George Krause decided the Sprint version was the Firebird he wanted, he ordered it with the optional four-speed transmission and gauge package that included a tachometer. Bill remembers the Sprint’s sticker price as being $2,300, but doesn’t recall what the dealer offered on his grandmother’s Olds trade-in.

The Firebird Sprint was the elder Krause’s daily driver from new until 1972, when it was replaced with a company car. Bill said the convertible was parked in his family’s garage, with fewer than 83,000 original miles, until he got his driver’s license in 1976, and was allowed to drive it sporadically.
When his parents moved to Florida in 2003, Krause said his dad gave him the Firebird. At that time, years of Minnesota’s harsh winter climate and liberal use of salt to combat slippery roads had taken a minor toll on the Firebird Sprint’s lower body panels. Krause added that the OHC six’s factory chrome moly piston rings had never seated correctly, and oil blow-by was a problem.

By mid 2008, Krause decided to have the convertible undergo what he termed “a near frame-off restoration.” For this work, he relied on Jeff Benzinger and Auto Body Plus to bring the Sprint back to its original shape. The project took approximately 12 weeks to complete. During that time, Krause enlisted friend Bob Wilson and, together, they tore down the OHC six and refurbished the engine.

In high school, Krause had rebuilt engines in several foreign cars he owned at the time, including a Triumph Spitfire, MGB and an Opel GT, the latter also having an overhead-cam engine, which gave him the confidence to rebuild his Sprint’s uncommon powerplant. Krause added that Wilson is “a Ford guy who knows Windsors and Clevelands,” but he was enthused about tearing into the Pontiac OHC six to learn something new.

Aside from the Sprint’s unique harmonic balancer, which Krause was able to salvage his original, finding parts to complete the rebuild was no problem. “I was stunned that Kanter [Auto Products of Boonton, N.J.] had everything I needed,” Krause said. He also credited Ames Performance Engineering of Spofford, N.H., and Gary Woodland of Utah as being great sources of parts for the Sprint six. “Woodland has a building full of OHC six parts.”

Krause also said that networking with the first-generation Firebird club was helpful when problems cropped up that stumped he and Wilson. The only real headache, he said, was at the end of the project and involved fine-tuning the OHC six’s Rochester carburetor. “There was a lot of fussing and fuming with the carb to get it right,” Krause said.

His Firebird Sprint underwent what Bill Krause described as a
“near frame-off restoration” to address minor rust issues. The
car’s interior was still in good shape after 83,000 miles, and needed
only its carpet replaced.

Enjoying the ride
Since his Firebird Sprint has returned to the road, Krause has been displaying it at local shows and enjoying cruise nights, especially in top-down weather conditions. He said he’s gotten stranded only one time due to a mechanical malfunction, that when the rubber hose connecting the fuel tank to the main steel line collapsed and the car starved for fuel.

“It ended up being a 17-cent fix and a $100 ride on a rollback,” Krause joked.

While his current restoration projects include both a vintage gas pump and a Ducati motorcycle, Krause said he has another Firebird project on his radar.

“I want to build a second-generation Firebird Formula into a resto mod,” Krause explained. It will have a V-8 for power, but more importantly, it will continue the Pontiac legacy began by his grandfather more than 75 years ago.

The Firebird Sprint has been restored, but retains its original black
convertible top. The steel wheels match the car’s Montreux Blue
paint and the authentic look includes Coker redline tires.

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