Honda S2000 AP2 - 2004

The 9,000 RPM Unicorn: Why the Honda S2000 Remains Unrivaled

The Engineering Statement

In an industry often driven by focus groups and marketing trends, the Honda S2000 stands as a rare exception: a car built by engineers, for engineers. Conceived to celebrate Honda’s 50th anniversary in 1999, the S2000 was led by Shigeru Uehara, the same visionary behind the NSX. Uehara famously noted that the development team deliberately minimized input from the marketing department to ensure the vehicle remained a "pure" sports car, untainted by compromise.

The project began with the 1995 SSM (Sport Study Model) concept. While the concept featured a 2.0-liter inline-five cylinder engine and an automatic transmission derived from the NSX, the production version pivoted to a layout that would define its legacy: a high-revving inline-four paired exclusively with a six-speed manual gearbox. The goal was to create a "Real Open Sports" car that could match the chassis rigidity of a coupe while delivering the visceral experience of a roadster.

The Heart: F20C and the 9,000 RPM Redline

The soul of the S2000 is the F20C engine. Displacing just 2.0 liters, this naturally aspirated four-cylinder powerplant produced 240 horsepower (247 hp in Japan), achieving a specific output of 120 horsepower per liter. This figure was a world record for a mass-production naturally aspirated engine, a title Honda held for over a decade until the Ferrari 458 Italia arrived in 2010.

To sustain its stratospheric 9,000 RPM redline, the engine utilized exotic materials and manufacturing techniques, including Fiber-Reinforced Metal (FRM) cylinder liners and forged aluminum pistons. In 2004, responding to North American demand for more low-end torque, Honda introduced the F22C1 (AP2) engine. By increasing the stroke, displacement grew to 2.2 liters, boosting torque to 162 lb-ft and lowering the redline to 8,000 RPM. Crucially, the European market retained the 9,000 RPM F20C engine for the entire production run (1999–2009), creating a unique divergence in global specifications.

The Bones: High X-Bone Frame

A convertible typically suffers from structural flex, often described as "cowl shake." To solve this, Honda developed the "High X-Bone Frame." This hybrid monocoque structure features a high central tunnel that connects to the front and rear side members in an "X" pattern. This design allowed the S2000 to achieve torsional and bending rigidity figures superior to many contemporary closed-roof sports cars, providing a stable platform for its double-wishbone suspension.

The chassis layout is technically "front-mid-engine," with the entire engine block positioned behind the front axle centerline. This resulted in a perfect 50/50 weight distribution and a low polar moment of inertia, granting the car its legendary turn-in response.

Evolution: Taming the Widowmaker (AP1 vs. AP2)

The early cars (1999–2003, chassis code AP1) earned a reputation for being unforgiving. The rear suspension geometry was prone to "bump steer," where the rear wheels would toe-out under compression, causing the tail to snap out suddenly during aggressive cornering.

For the 2004 facelift (AP2), Honda’s engineers significantly revised the suspension geometry, subframe, and spring rates to induce toe-in under compression, stabilizing the rear end. While the AP2 is faster and more predictable on a track, purists often prefer the raw, "on-edge" character of the AP1.

Special Editions and Collectibility

As production neared its end, Honda released several highly collectible variants:

S2000 CR (Club Racer): A US-exclusive track weapon with aggressive aero, a removable hardtop, and no radio or A/C, weighing roughly 90 lbs less than the standard model. Only 699 were produced.

S2000 RJ Edition: A tribute to Honda F1 drivers Rubens Barrichello and Jenson Button. Limited to just 50 units total across France, Italy, and Spain, these Pearl White cars feature the drivers' signatures on the radio door.

Ultimate Edition: The European swan song (2009), finished in Grand Prix White with red leather and graphite wheels.