Honda F20C: The 9,000 RPM S2000 Heart That Matched F1 Specific Output

When Honda revealed the F20C in 1999 — the 2.0-liter naturally-aspirated inline-four that would power the S2000 roadster — the specifications were almost unbelievable. 250 horsepower from 1,997 cc, without forced induction. That's 125 HP per liter, the highest specific output of any naturally-aspirated mass-production road car engine ever built. For context, the Ferrari F40's turbocharged 2.9-liter V8 made 163 HP per liter. Honda built an NA four-cylinder that approached Formula 1 specific output.

The F20C had to be built to redlined at 9,000 rpm, cooled to survive continuous high-RPM operation, and reliable enough to outlast any other sports car of its era. Honda delivered all three. This is the F20C.

Factory Specifications (F20C — AP1 S2000)

FRM Cylinder Liners: The Secret Weapon

The F20C has one of the most unusual cylinder block constructions in production car history. Instead of cast-iron or nickel-silicon-carbide liners, Honda used FRM (Fiber Reinforced Metal) — an aluminum-matrix composite with embedded ceramic fibers.

The benefit is extreme thermal conductivity and hardness. FRM liners transfer heat to the cooling jacket more efficiently than iron, allowing higher compression ratios and tighter piston-to-wall clearances. They're also extremely hard-wearing — F20C engines with 200,000+ miles routinely have near-zero cylinder wear when inspected.

The downside? You can't bore them. Standard overbore operations (hone, re-sleeve, oversize pistons) are impossible because the FRM material is harder than conventional boring tools. If an F20C cylinder wall is damaged, the entire block must be replaced. For this reason, rebuilders sometimes swap FRM blocks for later F22C1 (AP2) blocks, which use conventional iron liners and can be machined normally.

AP1 vs AP2: The Two Generations

F20C — AP1 (1999-2003)

The original. 2.0-liter, 9,000 rpm redline, 250 HP at 8,300 rpm, peaky power delivery. The AP1 S2000 is a VTEC screamer — there's almost no torque below 4,000 rpm, then a massive "VTEC kick" at 6,000 rpm that pulls hard to 9,000 rpm. Polarizing but unforgettable.

F22C1 — AP2 (2004-2009)

A revised variant. 2.2-liter displacement (87 × 90.7 mm bore/stroke — longer stroke for more torque), conventional iron cylinder sleeves (no FRM), 237 HP at 7,800 rpm, 162 lb-ft at 6,800 rpm, 8,000 rpm redline (down from 9,000). More mid-range torque, easier to drive, but less high-RPM character.

The JDM S2000 Type S, Club Racer, and S2000 CR variants all retained the F20C (or F22C) depending on year, but the F20C's reputation is most closely tied to the first-generation AP1.

VTEC on Both Cams: A New Level

The F20C was the first Honda engine to use VTEC on both the intake AND exhaust camshafts. Previously, B18C/B16B/K20A had VTEC only on the intake cam (the exhaust cam used a single fixed lobe profile). Adding VTEC to the exhaust cam allowed Honda engineers to optimize exhaust timing for both low-RPM efficiency (mild profile) and high-RPM scavenging (aggressive profile).

The result is an engine that makes more power at the top end than any conventional single-cam VTEC design, while retaining acceptable part-throttle fuel economy.

Known Weaknesses

1. Oil Consumption (The Infamous Problem)

Some F20C engines develop an oil consumption issue as they age. The cause is typically a worn piston ring or cylinder wall glaze from lugging the engine below 4,000 rpm. The fix is to drive the car regularly above 5,000 rpm, changing oil religiously, and in severe cases, an engine rebuild with new rings. Early-mileage F20Cs usually show no consumption; high-mileage examples often consume 1 quart per 1,000 miles.

2. Rod Bearing Wear (Rare)

Less common than on the EJ257, but possible. Caused by insufficient warm-up and aggressive driving. Proper warm-up and 5W-40 full synthetic prevent it.

3. Timing Chain Tensioner Rattle on Cold Start

Brief rattle on cold start is normal and benign. Persistent rattle indicates chain wear.

4. Heat Management

The F20C runs hot by design. The oil cooler and radiator are mandatory for any modified or track-driven car.

Real Tuning Limits (NA)

Famous Cars

Honda S2000 AP1 (1999-2003) — The hero car. Championship White, red Honda badge, rear-wheel drive, 6-speed manual, double-wishbone suspension. One of the best-handling production cars of its era. Approximately 65,000 AP1s produced worldwide.

Honda S2000 AP2 (2004-2009) — The "refined" version with F22C1 engine. More torque, easier to drive, but less revvy. Total AP2 production ~51,000 units.

Honda S2000 CR (Club Racer — 2008-2009) — The ultimate S2000. Lightweight removable hardtop, stiffer suspension, aero kit. USDM-only, 699 units built.

Factory Service Data

• Oil Change: 5,000 mi (8,000 km) normal; 3,750 mi for spirited/track
• Timing Chain: Non-serviceable (chain-driven)
• Spark Plugs: NGK IZFR6K-11 iridium
• Valve Clearance (cold): Intake 0.21-0.25 mm / Exhaust 0.28-0.32 mm
• Coolant: Honda Type 2 antifreeze

Conclusion

The F20C is the high-water mark of naturally-aspirated Honda engineering. It proved that a mass-produced four-cylinder could match the specific output of Formula 1 engines of its era. It powered the S2000 — the car that Top Gear's Jeremy Clarkson called "a perfect sports car" — for ten years. And it remains, to this day, one of the most revered four-cylinder engines ever built. When Honda kills the NSX and doesn't replace the S2000, the F20C becomes even more valuable as a reminder of what the company was once capable of.