What Is the Difference Between K24A and K24A2?
The first three characters tell you the family. The suffix tells you the engine.
The K24 variants at a glance
| Variant | Vehicle(s) | Key differences |
|---|---|---|
| K24A1 | Honda CR-V | Lower compression, different intake manifold, economy-focused tuning |
| K24A2 | Acura TSX | Higher-flow head, higher compression, performance-focused tuning |
| K24A4 | Honda Accord | Similar to A1, different accessory layout |
| K24A8 | Honda Element, some CR-V | Variant of the A1 family |
| K24Z | Later-model applications | Updated variants with different emissions and engine management |
Why the differences matter
The cylinder head is the primary differentiator. The A2 head flows more air and is paired with a higher compression ratio, which is why the TSX made more power than the CR-V from the same basic block. That is not just a tuning difference: the head, intake manifold and engine management are all different components.
Fitting a K24A1 where a K24A2 is expected means the intake manifold does not match, the ECU expects different parameters, and the accessory layout may differ. The reverse is equally problematic. These are not bolts-on differences.
The suffix is what you need
When you photograph the stamp on your engine, capture the entire code. "K24" tells a supplier the family. "K24A2" tells them the specific engine. The difference between those two levels of information is the difference between a part that fits and one that does not.
This applies to every engine family on this site, not just the K24. The suffix is where the specification lives.
Common questions
Can I use a K24A1 where a K24A2 is required?
Not without addressing the intake manifold, ECU and potentially the accessories. The two have different cylinder heads, different compression ratios and different engine management. A fitment check establishes exactly what is needed for your specific vehicle.
Which K24 is the most common replacement?
The K24A1 and its close variants, because the CR-V and Accord are among the most commonly replaced vehicles. The K24A2 is more specifically demanded by TSX owners, and supply can be thinner as a result.
Related pages
- K24 EngineThe 2.4 K-series from the Accord, CR-V, Element and TSX.
- Acura TSXThe most sought-after K24 variant, and what that means for buying one.
- Honda CR-VEvery modern CR-V is a K24, but which K24 changes by generation.
- Engine FinderTell us the vehicle and we identify the engine before quoting it.
- JDM Engine QuestionsAnswers to the questions Phoenix JDM engine buyers actually ask.
Find the right engine for your vehicle
Tell us the year, model and trim. We identify the engine your vehicle takes and come back with current availability and pricing.