If you’re looking at a Honda with a K-series engine or considering a swap, the Honda K24A8 engine is a unit you’ll want to understand. This comprehensive guide to understanding its specs and performance will give you the full picture.
It’s a common engine found in popular models, known for its balance of reliability and potential. Let’s break down everything that makes this powerplant tick.
Honda K24A8 Engine Specs and Performance
The K24A8 is a 2.4-liter, inline-four cylinder engine part of Honda’s renowned K-series family. It was introduced in the 2002-2008 Honda Accord (7th generation) for the North American market, specifically in the LX and SE sedan models. Unlike some of its more powerful siblings, the A8 was designed with a focus on everyday drivability and efficiency.
Detailed Technical Specifications
Here are the core technical specs that define the K24A8 engine:
* Engine Code: K24A8
* Displacement: 2.4 liters (2354 cc)
* Bore x Stroke: 87 mm x 99 mm
* Compression Ratio: 9.7:1
* Valvetrain: DOHC (Dual Overhead Cam) with i-VTEC
* Cylinder Block: Aluminum with cast-in iron liners
* Cylinder Head: Aluminum
* Fuel System: Multi-Point Fuel Injection (PGM-FI)
* Horsepower: 160 hp @ 5500 rpm
* Torque: 161 lb-ft @ 4500 rpm
* Redline: 6800 rpm
Key Design Features
The K24A8 shares the fundamental architecture of the K-series. This includes a deep-skirt aluminum block for strength, a dual-stage oil pump, and a timing chain for durability. Its 87mm bore and long 99mm stroke give it a characteristic that favors torque in the lower and mid rpm ranges, which is perfect for a daily-driven sedan.
The cylinder head uses Honda’s i-VTEC system. However, it’s crucial to note that on the K24A8, i-VTEC only operates on the intake camshaft. It adjusts valve timing and lift for a blend of efficiency and power, but it does not have the more aggressive VTEC “kick” on the exhaust side that higher-performance K-series engines are known for.
Performance Characteristics and Driving Experience
So, what’s it like to drive a car with the K24A8? The performance is best described as smooth and competent. The 160 horsepower and 161 lb-ft of torque provide adequate power for merging and highway driving. The torque curve is flat and accessible, meaning you get good pull from around 2000 rpm without needing to rev the engine highly.
It’s not a speed demon, but it offers a linear and predictable power delivery. The engine pairs with either a 5-speed manual or a 5-speed automatic transmission in the Accord. The manual offers more engagement, allowing you to better utilize the available power band.
Comparing the K24A8 to Other K24 Engines
The K-series family is vast, and the A8 is often compared to its brothers. Here’s how it stacks up:
* vs. K24A2 (TSX): The A2 is the performance cousin. It has a higher 10.5:1 compression ratio, more aggressive camshafts, and i-VTEC on both intake and exhaust. This results in 200 horsepower. The A2 also has a better flowing intake manifold.
* vs. K24A4 (CR-V, Element): The A4 is very similar to the A8 but tuned for SUVs. It has a slightly different intake manifold and exhaust manifold for more low-end torque, though power figures are identical.
* vs. K24Z3 (Later Accords, Civics): The Z3 represents a newer design with revised internals and a higher redline. It typically produces more power, around 180-200 hp, depending on the application.
The main takeaway is that the K24A8 is a solid, base-model engine. It lacks some of the high-performance parts of other K24s but shares their legendary reliability and basic structure.
Common Modifications and Tuning Potential
While not the first choice for big power builds, the K24A8 has a strong aftermarket following due to its low cost and strong bottom end. Here are common upgrade paths:
1. Cold Air Intake & Exhaust: Simple bolt-ons to improve throttle response and sound.
2. Header: Replacing the restrictive factory exhaust manifold with a aftermarket header is one of the best bang-for-your-buck mods for these engines.
3. ECU Tuning: A reflash or standalone ECU can optimize air/fuel ratios and ignition timing, especially after other mods are installed.
4. Intake Manifold Swap: Many people swap the A8 manifold for a more aggressive one from a K24A2 or even a RBC manifold from a later Accord. This requires some adaptation but improves high-RPM airflow.
5. Forced Induction: The block can handle moderate boost from a turbocharger or supercharger kit with proper supporting mods (fueling, tuning, and often lower compression pistons).
Remember, the 9.7:1 compression ratio is a bit lower than other K24s, which can actually be beneficial for turbocharging. However, the stock rods and pistons are the weak point for high-power applications.
Reliability, Common Issues, and Maintenance
The K24A8 is famously reliable when properly maintained. It’s not uncommon to see these engines reach 250,000 miles or more. That said, it has a few known issues to watch for:
* VTC Actuator Rattle: A common problem on many K-series engines. On cold start, you might hear a brief rattling sound from the front of the valve cover. This is the Variable Timing Control actuator failing. It’s more of an annoyance than a critical failure.
* Oil Consumption: Some engines may begin to consume oil due to worn piston rings or valve stem seals as they age. Regular oil level checks are advised.
* Timing Chain Tensioner: While the chain itself is robust, the automatic tensioner can sometimes fail. A failing tensioner may cause a rattling noise from the timing cover.
A strict maintenance schedule is key to longevity. Use high-quality synthetic 5W-20 or 5W-30 oil and change it every 5,000 miles. Replace the timing chain and tensioner if any noise appears, and keep up with coolant and spark plug changes.
The K24A8 as a Swap Candidate
In the world of engine swaps, the K24A8 is a popular and cost-effective option. Its lower purchase price makes it attractive. Swappers often use the A8 block and combine it with a more performance-oriented cylinder head from a K20 or K24A2. This “Frankenstein” build creates a high-displacement, high-revving engine with excellent power potential.
The wiring and ECU can be tricky, but standalone engine management systems have made this process much simpler. It’s a great way to add modern, reliable power to older Hondas or even other lightweight rear-wheel-drive cars.
FAQs About the Honda K24A8 Engine
Q: What cars came with the K24A8 engine?
A: It was used exclusively in the 2002-2008 Honda Accord LX and SE sedans (7th generation) in the United States and Canada.
Q: Is the K24A8 a VTEC engine?
A: Yes, but it uses i-VTEC only on the intake camshaft. It doesn’t have the classic high-RPM “VTEC crossover” feel of a performance Honda engine.
Q: Can you turbo a K24A8?
A: Absolutely. The block is strong, but for significant boost, you should upgrade the internal components like pistons and connecting rods for safety. The lower compression ratio is a good starting point.
Q: How much horsepower can a stock K24A8 handle?
A: On a stock bottom end, a reliable and safe limit with a good tune is generally considered to be around 300-350 horsepower with forced induction. Pushing beyond that risks damaging the rods and pistons.
Q: What’s the main difference between a K24A8 and a K24A2?
A: The A2 has a higher compression ratio, more aggressive camshafts, i-VTEC on both cams, and a better intake manifold. This gives the A2 about 40 more horsepower.
Q: Is the K24A8 a good engine?
A: Yes, it’s an excellent engine. It’s incredibly reliable, has good low-end torque for daily driving, and has a huge aftermarket for parts and support. It may not be the most powerful K24, but it’s a fantastic foundation.
Final Thoughts
The Honda K24A8 engine is a testament to Honda’s engineering philosophy: practical, efficient, and overbuilt. While it may not have the headline-grabbing power figures of its siblings, it delivers a dependable and enjoyable driving experience. Its real value lies in its durability and its role as a gateway into the world of K-series performance.
Whether you’re maintaining your Accord, planning some bolt-on mods, or sourcing a block for a ambitious swap project, the K24A8 is a platform with proven credentials. Understanding its specs and performance characteristics is the first step to making the most of this capable powerplant. With proper care and maybe a few upgrades, it can provide service and smiles for hundreds of thousands of miles.