![squish. squish.](https://http2.mlstatic.com/D_NQ_NP_720206-MLB46641667230_072021-W.jpg)
^ a b Wu, Horng-Wen Perng, Shiang-Wuu (May 2002).^ a b "The Combustion Chamber" Retrieved 16 June 2013.^ "How to Measure Your Cylinder Head Squish Clearance." Retrieved 16 June 2013.This affects how the whole engine runs and the intake and exhaust velocity that in produced. There are also ways to modify the piston and give it intake and exhaust squish areas.
![squish. squish.](https://ae01.alicdn.com/kf/HTB1vYwxXx_rK1RkHFqDq6yJAFXau/Squishy-fruta-squish-morango-barato-lento-subindo-squeeze-telefone-cinta-charme-pingente-squishes-macio-scented-brinquedo.jpg)
When looking at engines with more valves and different injector locations there are many different designs that increase the efficiency of the engine. However this is only one design for a diesel engine. This is where the squished air is mixed with the fuel from the injector creating a more evenly mixed air–fuel ratio. This design directs air from the squish area into the centre of the combustion chamber. It also requires a curve on the outer section of the piston crown. To promote turbulence and mixing of the air–fuel mixture, the piston crown must have a recess parallel to the angle that the fuel is injected. This creates a different type of turbulence that goes down instead of up in the piston itself. Others may use raised areas relative to the piston rings to create a different effect in the combustion chamber. These pockets can be made by making a recess in the piston crown. This is the most common way to create a squish piston engine because it is the smallest and easiest part to manufacture. Modified piston squish piston engines utilise a space in the piston to create an air pocket for squishing and combustion to occur. This design is mostly used in small, low cost applications. These types of engines are not very common anymore because of the inherent issues with insufficient air flow into the engine which directly affects the compression ratio. These squish piston engines are otherwise referred to as flat head engines.
![squish. squish.](https://http2.mlstatic.com/D_NQ_NP_960449-MLB30353644672_052019-O.jpg)
Modified block squish piston engines utilise a space in the block to create a pocket for squishing and combustion to occur.
![squish. squish.](https://images.tcdn.com.br/img/img_prod/808210/bichinho_mini_squish_macio_silicone_satisfatorio_fidget_toy_antistress_importado_62075607_1_63345d44a52b4d70aa088adbf9c8348f.jpg)
Modified head squish piston engines can also be made to fit the application on a flathead engine as well as overhead camshaft and two stroke engines. Depending on the shape of the pocket and what type of engine, the valve position must be skewed to ensure that both the intake and exhaust valve can fit in the pocket. Modified head squish piston engines utilise a space in the head to make an air pocket for squishing and combustion to occur. These combinations are used when certain design parameters that attribute the shape and constraints of the combustion chamber. Some engine designs include combinations of these different design types. Squish piston engines are achieved by modifying an engine's head, block, or the piston crown. This efficiency and swirling can also reduce the amount of soot production. Heat transfer is aided when the combustion gasses swirl around and heat the cylinder wall and the cooling system more efficiently. Turbulence in the combustion chamber due to this squish helps with air-fuel mixing, cylinder wall heat transfer, thermal efficiency, and overall engine performance. Squish piston engines are also found in both two stroke and four stroke engines. Squish effect may be found in any fuel type internal combustion piston engine. Squish effect may be found in side-valve, OHV and OHC engines, including engines with a Heron cylinder head. The gases are suddenly "squished" out within the combustion chamber, creating turbulence which promotes thorough air-fuel mixing, a factor beneficial to efficient combustion. In an engine designed to use the squish effect, at top dead centre the piston crown comes very close (typically less than 1 mm ) to the cylinder head. Squish is an effect in internal combustion engines which creates sudden turbulence of the air-fuel mixture as the piston approaches top dead centre (TDC).