Oil pressure

Oil pressure: Pressure to circulate engine oil. 200 kPa or less at 4000 rpm or more is a sign of engine trouble.

Oil pressure gauge is a meter that measures the pressure of engine oil circulating in the engine. The guideline for idling is 100-200 kPa, and oil pressure varies considerably depending on the viscosity of the oil.

Trouble due to low oil pressure can be caused by a variety of factors, including:

Viscosity drops due to high oil temperature.
When starting from 0-400
When cornering at a circuit, oil in the oil pan may become uneven.
Oil is less than the specified amount, etc.

It is important to check oil pressure at high RPM in advance to prevent problems. Automobiles with large oil pressure fluctuations due to oil bias may require baffles in the oil pan to prevent.

Oil pressure varies depending on the viscosity of the oil. In particular, the idling value changes sensitively when the oil temperature is low, so be careful when changing oil viscosity or brand, so you can see and enjoy the difference!

OIL PRESSURE GAUGE

Products displaying Oil Pressure	Defi Sports Display F ADVANCE FD (Sensors must be purchased separately) ADVANCE Oil Pressure Gauge DIN-Gauge Racer Gauge Pressure Gauge
Display Range	0kPa～1000kPa（1kgf/cm²=98.07kPa）
Guideline for Warning Point	120kPa *Warning Points vary depending on the car model and oil.
Parts that need be purchased separately	Sensor attachment (screw size 1/8PT) Sealing tape
Recommended sensor installation position	Install the sensor attachment at the oil element installation position.

Relationship between engine oil and oil pressure

If the oil pressure gauge indicates 100 kPa or less at idling when the oil and water temperatures are above 100°C, it is a dangerous condition. However, since most genuine oils these days have low viscosity and are softer due to the trend toward greater fuel efficiency, it is normal for the oil pressure gauge to show less than 100 kPa for some car models.

Successive generations of Defi demo car Lancer Evos used stock oil 10W-40. Under conditions of 900 rpm engine speed and 88°C oil temperature, the oil pressure was 80 kPa. When slightly harder 15w-50 oil was used, the oil pressure increased to 100 kPa under idling conditions.

Oil pressure gauges are useful for oil selection and when to change the oil. When driving on a circuit, it is important to know the usual conditions of the car, such as oil temperature, oil pressure, water temperature, and engine RPM.

The graph below shows that 2 is a higher performance oil than 1.

Cautions for sensor installation

Defi recommends installing the sensor by inserting a commercially available attachment between the engine and the oil filter.
It is recommended that measurements be taken behind the oil pump (e.g., at the same location as the factory oil pressure sensor), but in some car models, the factory sensor may be directly attached to the oil pump. In such cases, the pressure may momentarily reach 30.0 x 100 kPa (meter scale, three times the sensor’s sensing range), which may damage the sensor.
To prevent problems during installation, it is recommended to use a commercially available sensor attachment.