Oiling Systems

Does your oil pressure drop in long corners, or does your engine need more lubrication after a higher-boost project? This category brings together the parts that move oil through the engine: oil pumps, filters and filter adapters, oil pans, oil pickups and dry sump systems with oil tanks. For you who build engines for the street, track or off-road.

How the oiling system works

The oil pump draws oil from the oil pan through the oil pickup and sends it through the filter on to the bearings, camshaft and turbo, if fitted. In long corners and under hard braking, the oil can slosh away from the pickup, so the pump briefly draws air. An oil pan with baffles or trap doors can counteract this. Dry sump systems can solve the problem more fundamentally, because an external pump draws the oil out of the pan and sends it to a separate oil tank.

How to choose pump and filter

An oil pump must match the specific engine code, e.g. 4G63, SR20DE/DET or EJ20/EJ22/EJ25. Some pumps only fit certain market versions of an engine, so check the product description. Higher pump capacity is not automatically better: it should be matched to bearing clearance, oil viscosity, rpm and the pressure relief valve that limits the pressure. For oil filters and filter adapters, the choice depends on thread, gasket diameter and available space. Depending on the model, a filter adapter can make it possible to relocate the filter or connect an oil cooler and gauges. Brands in the category include K&N Engineering, ProFilter, Moroso, Peterson Fluid Systems and Boundary.

Installation and first start-up

The oiling system is closely tied to the rest of the engine. If you are also replacing bearings or the crankshaft, the pump, pickup and oil pan should be chosen so they work together. A new oil pickup must sit at the correct distance from the bottom of the oil pan, and bolts and gaskets should be tightened according to the manufacturer's instructions. With a dry sump system, the oil tank, hoses and fittings are positioned so the hoses stay clear of heat and moving parts. After installation, you should build oil pressure before starting the engine, and then check for leaks.

Frequently asked questions

When does a dry sump system make more sense than a baffled oil pan?

Typically when the car is exposed to high and sustained G-forces, e.g. on track, or when the engine needs to sit lower. A baffled oil pan is simpler to install, while a dry sump requires an external pump, oil tank, hoses and more space.

What does the pressure relief valve do in the oiling system?

It opens when the oil pressure reaches a certain limit and routes excess oil back. The spring in the valve determines the opening pressure, so changing it affects oil pressure and should be matched to the pump, bearing clearance and oil.

Can I use any oil filter as long as the thread fits?

Not necessarily. Gasket diameter, filter length, built-in anti-drainback valve and bypass valve can vary from filter to filter. So compare the specifications with the engine's original filter, and check the space around the filter mount.

What should I check after installing a new oil pump?

Build oil pressure before starting the engine, e.g. by cranking it without ignition, if possible. Then check the oil pressure at idle and with the engine warm, and look for leaks at gaskets and the filter.