Honda K24z3 Engine Specs And Performance – Comprehensive Guide To Understanding

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If you’re looking for a reliable and highly tunable four-cylinder engine, the Honda K24Z3 is a fantastic place to start your research. This guide will give you a complete breakdown of the Honda K24Z3 engine specs and performance, from its factory design to its potential on the road and track.

Honda K24Z3 Engine Specs and Performance

The K24Z3 is a 2.4-liter inline-four gasoline engine that belongs to Honda’s renowned K-series family. It was produced from 2007 to 2011 and served as the powertrain for several popular models. It’s known for its smooth power delivery, robust construction, and a huge aftermarket support network.

This engine is often considered one of the last purely mechanical, high-revving Honda engines before a stronger shift to efficiency-focused designs. Let’s break down what makes it tick.

Detailed Technical Specifications

Here are the core factory specifications for the Honda K24Z3 engine. These numbers form the baseline for all its performance characteristics.

  • Displacement: 2.4 liters (2354 cc)
  • Bore x Stroke: 87 mm x 99 mm – This is a classic “undersquare” or long-stroke design, favoring torque.
  • Compression Ratio: 10.5:1
  • Valvetrain: DOHC (Dual Overhead Camshaft) with i-VTEC
  • Cylinder Block: Aluminum with cast-in iron cylinder liners
  • Cylinder Head: Aluminum, with a “square” port design
  • Fuel System: Multi-point fuel injection (PGM-FI)
  • Redline: 7100 RPM
  • Factory Horsepower: 197 hp @ 7000 RPM (in the 2009-2011 Acura TSX)
  • Factory Torque: 172 lb-ft @ 4400 RPM (in the 2009-2011 Acura TSX)

Where You’ll Find the K24Z3

This engine wasn’t used in a huge range of vehicles, but its applications are notable. Knowing which car it came from helps you understand its stock tuning and potential donor vehicles.

  • 2009–2011 Acura TSX: This is the primary and most common source. These cars provide the complete engine, wiring harness, and ECU.
  • 2007–2008 Honda Accord (Japanese Market – CL9): The earlier version of the Euro/Japanese Accord also used this powerplant.

Key Design Features and Components

The performance of any engine comes down to its design. The K24Z3 has several features that contribute to its capabilities and reputation.

The i-VTEC System

The K24Z3 uses Honda’s intelligent VTEC system. Unlike the more aggressive VTEC found in performance engines like the K20A, the Z3’s i-VTEC focuses on a balance of efficiency and power.

It continuously varies valve timing on the intake camshaft (VTC) and switches between two distinct cam profiles on the exhaust camshaft. You feel a noticeable bump in power around 5500 RPM when the exhaust cam profile switches, though it’s less dramatic than the classic “VTEC kick.”

Cylinder Head and Port Design

The K24Z3 cylinder head is different from its high-performance siblings. It uses what’s often called a “square port” or “mid-port” design. The intake ports are smaller and more restrictive than the “RBC” or “RSP” heads found on other K-series engines.

This design prioritizes low-end and mid-range torque, which is great for daily driving. However, it becomes a restriction for high-RPM power in tuned applications. Swapping to a different K-series head is a very common upgrade.

Forged Internals and Block Strength

A major strength of the K24Z3, and most K-series engines, is its strong bottom end. The connecting rods are forged from the factory, which is a premium feature. The crankshaft is also forged.

The block itself is incredibly robust and can handle significant power increases on stock internals. This inherent strength is the main reason the engine is so popular for turbocharging and high-performance builds.

Stock Performance Analysis

In its stock form, the K24Z3 is a responsive and enjoyable engine. It’s not a tire-shredding monster, but it provides a very linear and usable powerband.

The long 99mm stroke gives it strong torque from low RPMs, making it feel peppy around town without needing to rev it out. The power builds smoothly to its 7100 RPM redline. The factory horsepower and torque figures translate to a car that feels quick and competent, with a 0-60 mph time in the mid-to-high 6-second range in the Acura TSX.

It’s a very reliable and efficient package for daily driving, with many examples exceeding 200,000 miles with basic maintenance. The engines are known for there durability when cared for properly.

Common Modifications and Tuning Potential

This is where the K24Z3 truly shines. Its strong foundation and vast parts interchangeability within the K-series family make it a tuner’s dream. Here’s a typical progression of modifications.

Stage 1: Basic Bolt-Ons

These mods improve airflow and free up a bit of power without opening the engine.

  1. Cold Air Intake (CAI): Improves intake airflow and sound.
  2. Exhaust System: A performance header (exhaust manifold) is the most impactful bolt-on. A cat-back system reduces backpressure.
  3. Throttle Body Upgrade: A larger bore throttle body from another K-series (like the 70mm from a K20) can help.
  4. ECU Tune: A custom tune (via Hondata FlashPro or K-Tuner) is essential to optimize these mods. This alone can wake the engine up significantly.

Stage 2: Cylinder Head Swap

To really unlock high-RPM power, many swap the restrictive Z3 head. The most popular swap is using a cylinder head from a K20A2 (from an RSX Type-S) or a K20Z3. This gives you larger, more aggressive ports and higher-lift camshafts.

This “K24/K20 hybrid” or “Frankenstein” build combines the K24’s torque-rich bottom end with the K20’s high-RPM breathing ability. It’s a legendary combination for naturally aspirated power, often reaching 230-250 whp.

Stage 3: Forced Induction

The forged rods make the K24Z3 an excellent candidate for turbocharging or supercharging. On a completely stock internal engine, 350-400 wheel horsepower is a conservative and reliable goal with a proper tune and supporting fuel system.

Key components for a turbo build include:

  • Turbo kit or manifold and turbo selection
  • Upgraded fuel injectors and fuel pump
  • An intercooler
  • A robust clutch
  • A comprehensive standalone or reflashed ECU tune

Common Issues and Reliability Concerns

No engine is perfect, and the K24Z3 has a few known weak points to be aware of. Thankfully, they are generally minor and well-documented.

  • Oil Consumption: Some engines, especially those driven hard, may consume oil past the piston rings. Using high-quality oil and checking it regularly is key.
  • VTC Actuator Rattle: A common issue on cold starts. The Variable Timing Control actuator can wear, causing a loud rattling noise for 1-2 seconds on startup. It’s more annoying than harmful, but replacement fixes it.
  • Motor Mounts: The factory hydraulic mounts can wear out and become soft, leading to excess engine movement during shifts.
  • Spark Plug Tube Seals: These can leak oil into the spark plug wells, which is a simple but important fix to prevent misfires.

Overall, with routine oil changes using the correct viscosity (typically 0W-20 or 5W-20) and timely maintenance, the K24Z3 is exceptionally reliable. It’s lack of complex direct injection or extreme turbocharging from the factory contributes to its longevity.

K24Z3 vs. Other Popular K-Series Engines

It’s helpful to see how the Z3 compares to its siblings.

  • vs. K20A2 (RSX Type-S): The K20A2 revs higher (8000 RPM redline) and has a more aggressive VTEC system and better cylinder head. It makes more peak power but less low-end torque than the K24Z3.
  • vs. K24A2 (Accord/TSX): The earlier K24A2 is very similar but has a slightly lower compression ratio and different intake manifold. The Z3 is generally considered a minor refinement.
  • vs. K20Z3 (Civic Si): The Civic Si engine is another high-revving, head-strong motor. The K24Z3 offers more displacement and torque, making it often prefered for street-driven cars or swaps where low-end grunt is desired.

Swapping the K24Z3 into Other Vehicles

This engine is a top choice for engine swaps due to its power, size, and compatibility. The most common swap is into the older Honda Civic (especially the EK and EP chassis) or the classic Acura Integra.

The process involves:

  1. Sourcing a complete engine, wiring harness, and ECU.
  2. Using aftermarket engine mounts (Hasport or Innovative Mounts are popular).
  3. Integrating the wiring with the donor car’s chassis harness (or using a standalone wiring solution).
  4. Upgrading the transmission, axles, and clutch to handle the power.

The result is a lightweight car with excellent power-to-weight ratio and Honda reliability. The aftermarket support for these swaps is massive, with detailed guides and kits available for almost any chassis.

Maintenance Schedule and Tips

Keeping your K24Z3 healthy is straightforward. Follow these guidelines to ensure it lasts.

  • Oil Changes: Every 5,000-7,500 miles with a quality synthetic oil and OEM filter.
  • Spark Plugs: Replace with OEM-spec iridium plugs every 60,000-100,000 miles.
  • Timing Chain: The chain is designed to last the life of the engine, but the tensioner and guides should be inspected if you hear unusual rattling.
  • Valve Adjustment: Check and adjust valve lash every 100,000 miles or if the engine becomes noticeably ticky.
  • Coolant: Flush and replace every 60,000 miles or 5 years.

Always use genuine Honda parts or high-quality equivalents for critical components like the oil filter and VTC actuator. This prevents many common issues from occuring in the first place.

FAQ Section

What is the difference between a K24A2 and a K24Z3?

The main differences are in the intake manifold, exhaust manifold, and a slight bump in compression for the Z3. The Z3 manifold is a two-part design, and the engine management is slightly more advanced. They are very similar in performance and potential.

How much horsepower can a stock K24Z3 handle?

With a proper tune and supporting fuel system, a stock internal K24Z3 can reliably handle around 350-400 wheel horsepower with forced induction. The forged connecting rods are the key to its strength.

Is the K24Z3 a good engine for a daily driver?

Absolutely. In fact, it’s excellent. It’s smooth, has plenty of low-end torque for easy driving, gets good fuel economy, and is known for its long-term reliability with basic care.

What is the best head to swap onto a K24Z3 block?

The K20A2 head (from the 2002-2006 RSX Type-S) is the most popular and well-supported choice for a high-performance naturally aspirated build. The K20Z3 head (from the 2006-2011 Civic Si) is also a great option.

Does the K24Z3 have VTEC?

Yes, it uses Honda’s i-VTEC system. It varies intake valve timing continuously and switches exhaust cam profiles. The changeover is noticeable but not as abrupt as in some older VTEC engines.

The Honda K24Z3 engine stands as a testament to Honda’s engineering during the 2000s. It offers a perfect blend of everyday usability and serious performance potential. Whether you’re keeping a TSX on the road, building a track monster, or swapping it into a lighter chassis, its strong specs, tunability, and proven reliability make it a perennially favorite choice. Understanding its design helps you make the most of this capable powerplant, ensuring you can enjoy its balance of torque, power, and durability for years to come.