If you’re looking for a reliable and tunable four-cylinder engine, the Honda K24A4 is a fantastic place to start. This guide will give you a complete look at the Honda K24A4 Engine Specs and Performance, from its factory design to its potential for upgrades.
Found in popular models like the 2002-2008 Honda CR-V and the 2003-2007 Honda Element, the K24A4 is known for its durability and smooth power delivery. It’s a cornerstone of Honda’s K-series family, which is beloved by enthusiasts worldwide. Let’s break down everything that makes this engine special.
Honda K24A4 Engine Specs and Performance
At its heart, the K24A4 is a 2.4-liter, inline-four cylinder, naturally aspirated engine. It uses Honda’s i-VTEC system, which combines variable valve timing and lift on the intake camshaft. This technology helps balance good fuel economy with responsive power.
Here are the core technical specifications for the K24A4 engine:
* Displacement: 2.4 liters (2354 cc)
* Bore x Stroke: 87 mm x 99 mm – This “square” design favors torque.
* Compression Ratio: 9.7:1 – A relatively modest ratio, leaving room for forced induction.
* Horsepower: 160 hp @ 5500 rpm (in US-spec CR-V/Element applications)
* Torque: 161 lb-ft @ 4500 rpm
* Redline: 6800 rpm
* Valvetrain: SOHC i-VTEC (4 valves per cylinder)
* Block Material: Aluminum with cast-in iron cylinder liners
* Head Material: Aluminum
* Fuel System: Multi-point fuel injection (MPFI)
The engine’s design prioritizes low-end and mid-range torque, making it feel peppy in everyday driving situations. This is why it worked so well in utilitarian vehicles.
Detailed Performance Characteristics
The performance of the K24A4 is defined by its broad torque curve. You get strong pull from around 2000 rpm, which is perfect for around-town driving and light hauling. The powerband is very linear and predictable.
While 160 horsepower might not seem high by today’s standards, the engine’s real-world feel is excellent. The i-VTEC system engages noticeably, providing a surge of power in the mid-range. However, it’s not a high-revving monster like the twin-cam K20; it’s more of a strong, dependable workhorse.
Strengths of the K24A4 Design
Several key features contribute to the engine’s reputation:
* Closed-Deck Block: This makes the block structure very rigid and strong, an excellent foundation for handling increased power from turbocharging or supercharging.
* Forged Steel Crankshaft: It’s incredibly durable and can handle significant stress.
* Oil Jet Cooling: Pistons are cooled by oil jets from below, which helps manage temperatures and allows for more aggressive tuning.
* Chain-Driven Timing: This is a maintenance-friendly feature compared to interference engines with timing belts.
Common Applications and Vehicles
You’ll find the K24A4 engine in two primary Honda models:
1. 2002-2008 Honda CR-V (US Market): This was the main home for the A4. It provided the SUV with ample power for its size.
2. 2003-2007 Honda Element (US Market): The same engine suited the Element’s quirky, functional character perfectly.
It’s crucial to note that other global markets sometimes had different K24 variants with slightly higher output. Always check your vehicle’s specific engine code.
Comparing the K24A4 to Other K-Series Engines
The K-series family is large. Here’s how the A4 stacks up against some famous siblings:
* vs. K20A2 (from RSX Type-S): The K20A2 is a DOHC, higher-revving engine making 200 hp. It loves to be driven hard and revs past 8000 rpm. The K24A4 makes more torque lower down but has less peak horsepower.
* vs. K24A2 (from TSX): The A2 is the A4’s more powerful cousin. It has a higher 10.5:1 compression ratio, a more aggressive camshaft, and a dual-stage intake manifold, resulting in 200 hp. The blocks are very similar, making the A2’s parts popular upgrades for the A4.
* vs. K24Z3 (from later CR-V/Accord): The Z3 uses a different VTEC system and has slightly updated tech, but power figures are similar. The A4’s closed-deck block is often considered more desirable for big power builds.
Modification and Tuning Potential
This is where the K24A4 truly shines. Its robust bottom end and closed-deck block make it a favorite for swaps and power builds. The goal is usually to unlock the horsepower that Honda left on the table for economy and emissions reasons.
Basic Bolt-On Upgrades
Starting with simple mods can wake the engine up:
* Cold Air Intake (CAI): Improves airflow and engine sound.
* Performance Exhaust Header: Replacing the restrictive stock manifold is one of the best bang-for-buck mods for power.
* Cat-Back Exhaust System: Reduces backpressure and improves flow.
* Throttle Body Upgrade: A larger bore throttle body from a K24A2 can improve airflow.
* Engine Tune: This is essential after modifications. A reflash or standalone ECU tune adjusts air/fuel ratios and ignition timing to maximize gains from your bolt-ons.
Advanced Performance Builds
For serious power, builders often combine the K24A4 block with other cylinder heads and components:
* K24A4 Block + K20A2 Head: This popular “K24/K20 frankengine” combines the K24’s torque with the K20 head’s high-flowing ports and high-RPM capability. It’s a classic recipe for a naturally aspirated beast.
* Forced Induction: Turbocharging or supercharging is very common. The strong block can reliably handle 400-500 whp with the right supporting mods (fueling, internals, tuning).
* Internal Upgrades: For high-boost applications, you’ll need forged pistons and connecting rods. The stock crankshaft is usually strong enough for most builds.
Essential Supporting Mods
When increasing power, don’t forget these critical areas:
1. Fueling: Upgrade fuel pump, injectors, and fuel pressure regulator.
2. Clutch: The stock clutch will slip with added power. A performance clutch is a must.
3. Cooling: A larger radiator or oil cooler helps manage increased thermal loads.
4. Engine Mounts: Stiffer mounts prevent excessive engine movement under hard acceleration.
Common Issues and Reliability Concerns
No engine is perfect. Here are some things to watch for with the K24A4:
* Oil Consumption: Some engines, especially with higher mileage, can burn oil. This is often due to worn piston rings or valve stem seals.
* VTEC Solenoid Gasket Leaks: A common oil leak point. The gasket is cheap and easy to replace.
* Chain Tensioner Failure: While rare, a failing timing chain tensioner can cause a rattling noise on startup.
* Motor Mount Failure: The hydraulic engine mounts, particularly the rear, can wear out and cause vibration.
Overall, with basic maintenance—regular oil changes with quality 5W-20 or 5W-30 oil, timely tune-ups—the K24A4 is exceptionally reliable and can last well over 200,000 miles.
Swapping the K24A4 into Other Vehicles
The K24A4 is a premier choice for engine swaps due to its availability, low cost, and strength. It’s commonly swapped into lighter cars like the Honda Civic, Acura Integra, and even the classic Mini.
The swap process typically involves:
1. Sourcing a complete engine with wiring harness and ECU.
2. Getting custom engine mounts and shift linkage.
3. Upgrading the fuel system and cooling system.
4. Integrating the wiring, which is often the most complex part.
5. Tuning the ECU to work properly in the new chassis.
The result is a lightweight car with a huge increase in torque and power potential.
Step-by-Step Guide to a Basic Tune-Up
Keeping your K24A4 running smoothly is straightforward. Here’s a simple maintenance checklist:
1. Change the engine oil and filter every 5,000 miles.
2. Replace the spark plugs every 100,000 miles (iridium) or sooner.
3. Inspect and clean the air filter regularly.
4. Check the valve clearance every 100,000 miles—they usually stay in spec.
5. Replace the coolant every 5 years or 60,000 miles.
6. Inspect all belts and hoses for cracks or wear.
Doing these things will help ensure your engine stays healthy for the long haul.
Frequently Asked Questions (FAQ)
Is the Honda K24A4 a good engine?
Absolutely. It’s renowned for its durability, smooth power delivery, and massive tuning potential. Its strong closed-deck block makes it a favorite among modifiers.
What is the difference between K24A4 and K24A2?
The main differences are the cylinder head and intake manifold. The A2 has a higher compression ratio, more aggressive cams, and a dual-stage intake manifold, giving it 200 hp compared to the A4’s 160 hp. The blocks are very similar.
Can you turbo a K24A4?
Yes, it’s one of the best K-series blocks for turbocharging due to its closed-deck design. With proper fueling, tuning, and often internal upgrades, it can handle significant boost.
How much horsepower can a stock K24A4 handle?
The stock bottom end is robust. With a good tune, it can reliably handle around 300-350 wheel horsepower with forced induction. Pushing beyond that typically requires forged pistons and rods.
What cars did the K24A4 come in?
It was used primarily in the 2002-2008 Honda CR-V and the 2003-2007 Honda Element for the North American market.
Is the K24A4 an interference engine?
Yes, it is an interference engine. If the timing chain were to fail or skip time, the valves and pistons could collide, causing severe engine damage.
The Honda K24A4 engine proves that practical design can lead to legendary performance potential. From its humble role powering SUVs, it has become a hero in the tuning and swapping community. Whether you’re maintaining a stock CR-V or building a high-horsepower project car, understanding its specs and capabilities is the first step. With its blend of everyday reliability and weekend warrior strength, the K24A4 secures its place as a modern classic.