The built engine is running well but the addition of the oil temperature gauge has been educational. When on boost the engine oil gets very hot (north of 120 degC) very quickly. Decided not to run the new engine on track until an oil cooler was installed.
After accessing the options, an oil to water (coolant) heat exchanger was selected over an oil to air cooler due to:
- Simpler installation – an oil to water heat exchanger can be mounted closer to the engine to minimise length of oil lines. Also, there are already two radiators at the front of the car so mounting an oil to air cooler would be difficult
- Due to coolant being at 85-90 degC an oil thermostat is not required
- On a cold start the heat exchanger has the added benefit of heating the oil to bring it up to operating temperature quicker. Engine oil takes a lot longer than coolant to come up to temp
The Mocal Laminova C43 180mm core heat exchanger was selected. Mocal documentation states that the performance of the heat exchanger in cooling the engine oil is comparable to a typical 16 to 19 row oil to air 235 matrix cooler.
There is no room for a sandwich plate so an oil take-off plate was fabricated from 12mm aluminium plate and the oil filter was relocated using a remote oil filter mount.
The heat exchange was mounted to the left chassis rail. The hot coolant comes of the back of the head runs down the left side of the engine, through the heat exchanger, then into the radiator.
For the oil circuit, pressurised oil exits the block, passes through the heat exchanger, through the oil filter, and back into the block.
Bonnet louvers have also been installed. This will increase air flow through the radiator that now needs to deal with increase heat load of cooling the engine oil. Louvers also assist with reducing under bonnet temperatures and heat soak.
