Yes — not every Park Avenue model was supercharged. The supercharged powerplant was reserved for the Park Avenue Ultra, while the standard Park Avenue used a naturally aspirated 3.8-liter V6. This article explains which models had the supercharger, how to tell them apart, and what that means for performance.
Powertrain overview
The Buick Park Avenue lineup spans two generations of a premium front-wheel-drive sedan. The base (non-Ultra) Park Avenue used a naturally aspirated 3.8-liter V6 from the Series II family. The Park Avenue Ultra, the high-end variant, swapped in a 3.8-liter Series II V6 with a Roots-type supercharger, yielding noticeably more power and torque. Both configurations relied on a gas-fired V6 and common GM auto transmissions, but the Ultra’s forced induction gave it a performance edge.
Key engine and performance differences between base Park Avenue and Park Avenue Ultra:
- Base Park Avenue: 3.8-liter V6 Series II, naturally aspirated; roughly 200–205 horsepower with about 230 lb-ft of torque.
- Park Avenue Ultra: 3.8-liter Series II V6 with a Roots-type supercharger (engine code typically L67); roughly 240–250 horsepower with about 275–285 lb-ft of torque.
- Common elements: Both are front-wheel drive and typically paired with a GM automatic transmission; the Ultra’s extra power comes from the forced induction rather than a larger engine.
In short, if you’re evaluating a Park Avenue, the presence of a supercharger is a hallmark of the Ultra trim; standard Park Avenues are naturally aspirated.
Identifying a Park Avenue Ultra
If you’re trying to confirm whether a specific Park Avenue is the supercharged Ultra model, use these indicators to verify:
- Badges and exterior cues: Look for an “Ultra” badge on the trunk lid or fender area, which denotes the higher-end trim.
- Engine code and under-hood label: The engine code is typically L67 for the supercharged setup, versus L36 for the naturally aspirated 3.8L V6 in base models.
- VIN/RPO data: The vehicle’s VIN or the window sticker’s RPO (Regular Production Option) codes will list L67 if the car has the supercharged engine.
- Model-year window: The Ultra variant was offered in the late 1990s into the early 2000s, as Buick positioned Park Avenue Ultra as the performance-oriented flagship.
- Performance cues: A noticeable power advantage in acceleration compared with non-Ultra Park Avenues, reflecting the added horsepower and torque from the supercharger.
Conclusion: Spotting Ultra badges, an L67 engine code, or RPO data indicating a supercharged 3.8L confirms you’re looking at a Park Avenue Ultra.
Summary
The Buick Park Avenue lineage includes both naturally aspirated and supercharged variants. The standard Park Avenue used a 3.8-liter V6 without forced induction, while the Park Avenue Ultra employed a supercharged 3.8-liter V6 to deliver higher output. Identification hinges on badges, engine codes (L67 vs L36), and VIN/RPO information, with the Ultra slate appearing in the late 1990s through the early 2000s. If you’re shopping or researching, know that the Ultra is the only Park Avenue variant that is truly supercharged.