Est. 2003
Why are Piston Squirters beneficial?
-Piston squirters are found in engines that are constantly under extreme conditions, usually Race engines or those with Forced Induction.
-The job of the oil squirter is to keep the piston cooler. The oil is colder than the combustion chamber.
-Coolant only cools the sleeve of the combustion chamber, not the piston. This is why coolant cannot cool the pistons.
-Too hot of a piston will lead to preignition and knock which can damage the engine (fuel is igniting too much before TDC and this force is working againse the piston movement).
-Higher octane or cooler temperatures will cure preignition. 91 octane is the most we have in California and it is not good enough for high boost/high compression.
-Piston Oil Squirters are most valuable in endurance conditions, like road racing. They are not beneficial for drag racing so they may be blocked off to create less breaking points for oil pressure problems.
-Squirters can be added to an engine. They must be drilled into the main oil galley and positioned correctly for each piston. This is not something that is usually done because it is too much work if your engine did not come with them already. However, if your engine is NA and there is a Turbo version with squirters it might not be too difficult to add them.
-When installing aftermerket pistons make sure that the piston skirts are not going to touch the squirter nozzel, it will break them off.
How do Piston Squirters work?
-Piston squirters are composed of two parts, a nozzel to direct the oil and a banjo-type bolt with a spring inside of it.
-The squirter is drilled into the block below the bottom of the piston's stroke. The bottom of the bolt has a hole in it which descends into the main oil galley. The bolt also has two holes near the top, past the spring where the oil leaves the bolt and goes into the nozzel.
-The spring in the bolt keeps oil from entering the nozzel until higher rpm where pistons will become hot. There is no need for them at lower rpm because there is not a cooling necessity and they will be wasting valuable oil pressure.
-Oil pressure at higher rpm is not as valuable because the oil pump can create more pressure that the engine needs and it will bleed off the oil pressure itself if it is not being used by the squirters.
-A 40lb spring is commonly used. A general rule is that an engine generated 10lbs or oil pressure for every 1,000 rpm, so this squirter would fully activate around 4,000 rpm.
