Pistons for naturally aspirated engines and pistons for turbocharged engines
Piston design: differences in naturally aspirated and turbocharged engines
Have you ever wondered if pistons always look the same whether they are used in turbo engines or naturally aspirated engines?
Pistons are always subjected to high loads, no matter which engine they work in. But the nature of the load varies greatly, and that must be considered when designing pistons. The thickness of the material and other factors have a major influence on stability, mixture formation and much more. Here you can find out exactly what the differences are between pistons for turbo engines and pistons for naturally aspirated engines.
- 1. The differences between pistons for naturally aspirated engines and pistons for turbocharged engines
- 2. Why is piston design so important? – Significant load test for pistons
- 3. How important are the material and thickness of pistons for performance?
- 4. How do high speeds and friction impact pistons?
- 5. Perfect for boosting performance: the asymmetrical piston skirt from JE Pistons
- 6. Flat or curved piston crown: which piston goes in which engine?
- 7. Why are piston pins and piston pin eyes so important for durability?
- 8. Why are gas-nitrided piston rings primarily used in racing?
- 9. You want more?
The differences between pistons for naturally aspirated engines and pistons for turbocharged engines
Pistons always look very similar – whether for naturally aspirated engines or for turbocharged engines. Nevertheless, they have to meet different requirements and are therefore designed differently. Many people think that pistons for turbo engines are just a bit thicker than those for naturally aspirated engines. However, there are a few small but essential differences in the design. These affect the stability, the sealing, the mixture formation, the weight, and so on. Since both types of engine are subjected to completely different loads in terms of pressure, heat and rpm, the piston design is also adapted. This is the only way to ensure maximum durability and performance. Here you can find out what really matters for proper pistons!
How important are piston material and thickness for performance?
With engine power, cylinder pressure and heat also increase. Both pistons for naturally aspirated engines and pistons for turbo engines are therefore made with a special aluminum alloy. Apart from similar metallurgy, however, pistons for naturally aspirated engines and turbo engines have little in common. Since forced induction engines can quickly reach three times the horsepower of a naturally aspirated engine, the individual areas of the pistons are made thicker and the clearances are also increased. This ensures that the piston design operates within strength limits. But it is not only performance that determines the perfect design of a piston. The application and duty cycle are also decisive factors.
What do high RPM and friction mean for pistons?
Tuned naturally aspirated engines subject the piston to a similar load in the high RPM range as forced induction engines. The difference lies in how the load acts on the piston. That’s why special attention is paid to ensuring that the area of the pin bore is solid and stable. This prevents the pin from being pulled out of the piston.
At high RPM, friction occurs that severely limits performance. When designing pistons, unique skirt shapes and profiles are therefore used that reduce friction without compromising stability and ring sealing. The piston skirt and ring lands are optimized to minimize the surface area and thus reduce friction to the absolute minimum. Compared to a conventional piston, this lets you gain a hefty 10–20 hp.
