Continental IO-550-L Engine – Factory New or Rebuilt

The Continental IO-550-L is a powerful, fuel-injected 300 horsepower engine commonly installed under STC in the Cessna 210 Centurion family—most notably as part of the Atlantic Aero engine upgrade program. This engine delivers significantly improved climb rates, cruise speeds, and fuel efficiency over legacy IO-520 models.

Air Power, Inc. is the world’s largest Continental engine distributor and the factory’s preferred partner for certified and STC upgrade engines. We stock both factory new and factory rebuilt IO-550-L engines and assist with full configuration matching and documentation.

Primary Aircraft Compatibility

• Cessna 210 (Atlantic Aero STC conversion)
• Cessna T210 & P210 (in some non-turbo applications)
• Experimental and custom airframes requiring high-output performance

Engine Specifications

• Model: IO-550-L
• Power Output: 300 HP @ 2700 RPM
• Displacement: 552 in³ (9.05 L)
• Configuration: 6-cylinder, horizontally opposed, fuel-injected
• Compression Ratio: 8.5:1
• Weight: Approx. 470 lbs (varies by configuration)
• Fuel Type: 100/100LL aviation gasoline
• TBO: 1,700–1,900 hours

Critical Spec Question – Oil Cooler Size

The decongealing oil cooler flange length is a critical spec for IO-550-L installations. We will confirm with you whether your aircraft or STC requires a:

• 7.88-inch oil cooler interface (shorter flange)
• 8.88-inch oil cooler interface (longer flange – most common for Atlantic Aero Cessna 210 conversions)

This must match your airframe cooler and mounting bracket configuration. If you’re unsure, our team can help verify with your mechanic or installation drawings.

STC Performance Upgrade

The IO-550-L has become a go-to replacement for aging IO-520-L and TSIO-520 engines in Cessna 210s. It offers:

• Improved climb and cruise performance
• Lower fuel burn in cruise vs. legacy engines
• Simplified engine management (no turbocharging)
• Factory support and modern warranty coverage

Order with Confidence from Air Power

When you purchase an IO-550-L from Air Power, you gain access to:

• Factory-direct pricing and support
• New or rebuilt engine options
• Expert STC configuration matching
• Engine logbooks, documentation, and warranty registration

Contact our sales team today to confirm the correct configuration and receive a quote. We support certified installers, FBOs, fleet operators, and owner-pilots globally.