Description

k24a engine

The K24A engine is a highly respected powerplant in Honda’s K-series engine family, praised for its versatility, durability, and performance potential. The K24A series builds on the success of Honda’s smaller-displacement K20 engines but offers more torque and displacement, making it ideal for a range of uses from daily driving to high-performance tuning.

Here’s a more in-depth look at the K24A engine:

Technical Specifications:

• Engine Code: K24A (with variations like K24A1, K24A2, K24A3, etc.)
• Bore x Stroke: 87 mm x 99 mm
• Displacement: 2,354 cc (2.4 liters)
• Compression Ratio: Varies by model, usually between 9.7:1 and 11:1
• Fuel System: Multi-Point Fuel Injection (MPFI)
• Redline: Generally between 6,500 and 7,100 RPM depending on the model

i-VTEC System:

The i-VTEC (Intelligent Variable Valve Timing and Lift Electronic Control) system is one of the standout features of the K-series engines. This technology adjusts valve timing and lift to optimize both low-end torque and high-RPM power. In the K24A, i-VTEC allows the engine to have excellent drivability at low RPMs (good for fuel economy) while offering strong power delivery at higher RPMs.

There are two types of i-VTEC systems used in K24A variants:

1. Low-Cam i-VTEC: Found in lower-performance versions like the K24A1. It switches between different cam profiles for intake valves, improving fuel efficiency and smoothness.
2. High-Cam i-VTEC: Found in higher-performance versions like the K24A2. It activates higher lift and longer duration cam profiles at higher RPMs, giving better high-end power.

Engine Block & Internals:

• Block Material: Aluminum with cast-iron cylinder liners, offering a balance of weight savings and durability.
• Crankshaft: Forged steel, built to handle the stresses of high-revving and performance driving.
• Connecting Rods: Typically made from high-tensile steel, they are durable but can be upgraded in performance builds.
• Pistons: The K24A uses aluminum pistons, which vary slightly depending on the variant and intended use (lower compression for economy models, higher for performance models).

Popular Variants:

1. K24A1:
   • Found in: Honda CR-V (2002–2006)
   • Power: 160 hp @ 6,000 RPM, Torque: 162 lb-ft @ 3,600 RPM
   • Compression Ratio: 9.6:1
   • Features: Basic i-VTEC system for fuel economy and smooth power delivery.
2. K24A2:
   • Found in: Acura TSX (2004–2008)
   • Power: 200-205 hp @ 6,800 RPM, Torque: 164 lb-ft @ 4,500 RPM
   • Compression Ratio: 10.5:1
   • Features: High-performance i-VTEC with a more aggressive cam profile. This is one of the most sought-after K24 variants for tuning.
3. K24A3:
   • Found in: Honda Accord (Europe, Australia)
   • Power: 188-190 hp @ 6,800 RPM, Torque: 171 lb-ft @ 4,500 RPM
   • Compression Ratio: 10.5:1
   • Features: Similar to the K24A2 but used in international markets.
4. K24A4:
   • Found in: Honda Accord (2003–2007), Honda Element (2003–2006)
   • Power: 160 hp @ 5,500 RPM, Torque: 161 lb-ft @ 4,500 RPM
   • Compression Ratio: 9.7:1
   • Features: A more economy-oriented variant, using the simpler low-lift i-VTEC system.
5. K24A8:
   • Found in: Honda Accord (2006–2007)
   • Power: 166 hp @ 5,500 RPM, Torque: 160 lb-ft @ 4,000 RPM
   • Compression Ratio: 9.7:1
   • Features: Slightly improved over the K24A4, with some minor revisions for better fuel efficiency and emissions.

Performance Potential:

The K24A is widely regarded as a strong platform for performance upgrades. Its design allows for high-revving characteristics while maintaining reliability. The block is robust enough to handle significant power increases with the right upgrades. Some enthusiasts swap K20 cylinder heads onto K24 blocks (commonly known as a K20/K24 Frankenstein build) to take advantage of the high-revving K20 head design combined with the larger displacement of the K24 block.

Turbocharging and Supercharging:

The K24A is also popular for turbocharging due to its relatively low compression ratio in some variants. With proper tuning, stock internals can handle modest levels of boost (around 300 hp), but for higher power levels, upgrading components like pistons, rods, and the fuel system is recommended.

Common Upgrades:

• Intake and Exhaust: Upgraded intake manifolds and exhaust systems are popular entry-level modifications to improve airflow and add horsepower.
• Cams: For naturally aspirated builds, performance camshafts can help unlock more power by improving the i-VTEC switchover and increasing valve lift.
• ECU Tuning: Many enthusiasts opt for standalone engine management systems or reflash the stock ECU to adjust fuel and ignition maps for better performance.
• Forced Induction: Turbo or supercharging the K24A can result in significant power gains, often exceeding 400-500 hp with built internals.

Advantages of the K24A Engine:

• Torque: The 2.4L displacement provides more low-end torque compared to smaller K-series engines, making it more suitable for street driving and daily use.
• Tuning Potential: Whether naturally aspirated or boosted, the K24A responds well to performance modifications.
• Durability: With proper maintenance, these engines can last well over 200,000 miles.
• Aftermarket Support: There’s a large aftermarket for K-series engines, making parts and knowledge readily available.