555 Engineering Oil Pressure Monitoring (On Track)

Oil Pressure Logs from baseline setting on a stock car

The data above shows that overfilling definitely improved average oil pressure, but did not have a noticeable effect on reducing "low pressure events" (essentially the same within margin of error across 3 sessions).

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You might also notice that the original Thunderhill datalogs had more frequent oil pressure drops. This is likely due to the much grippier and wider tire (which generates more G's) that was used in the Thunderhill datalogs vs the stock-ish tires used at our Sonoma session. 

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• The 3000 rpm / 33 psi minimum is a factory service manual minimum at 185F. Low pressure events recorded here are all above 185F. It is normal that nominal oil pressure drops with higher oil temperature (the oil becomes less thick [viscous] as it gets hotter and the pressure naturally drops).
• It is quite possible that the minimum oil pressure is actually lower than 33 psi at our datalogging range 200F - 270F and the lower values we are seeing are fine. 
• There are no published factory oil pressure minimums at higher temperatures, so this is all we have to go off of.  
• We did not compensate for viscosity differences from Oil temperature difference between cars and sessions. Values shown are the raw sensor measurements. 
• The Sonoma session has driver variables. The +.5 quart overfill car was observed to be typically braking later / harder.
• Sonoma vs Thunderhill has driver variables. Thunderhill driver is a faster / more aggressive driver.
• These datalogs are missing g sensor telemetry which is key information. Future comparisons will need to include this. This would help mitigate the driver variable in the comparison.
• Oil Pressure is read at the Oil filter plate via the OEM pressure/temperature sensor.
• Data was collected at 10 Hz (every .1 seconds) via factory CAN bus.

 

Our takeaway: 

We think this is a non issue for street cars. For novice-intermediate track users on OEM-ish tire setups it is worth noting but there is no danger of impending engine damage. The durations of the pressure drops are short. Most wet sump engine setups (ie LS engines are infamous for this and this is a nothing burger compared to the Porsche M96/97 motors) will have pressure drops like this on track. The OEM design goal is to keep it to a level that does not increase bearing wear which we assume Toyota engineered to with the amount of grip the factory tire setup can generate with some additional safety margin. If oil reports do not indicate increased bearing wear, there is no cause for concern.

 

Short durations of low oil pressure at the oil filter plate for a few tenths of a second does not necessarily mean instantaneous low oil pressure at the main bearings / critical friction surfaces or that the lubrication film protecting those areas are gone instaneously. However, longer low pressure durations could be reason for concern (super grippy tires and a fast driver).

 

For advance (ie open passing, time trials) track users who have increased power levels and sticky tires it might be worth taking this into closer consideration. There have been reports in the GR Yaris community with oil starvation issues on higher level builds. There is currently a single oil baffle on the market for the G16E-GTS but there is no published data to indicate how effective it is. On the otherhand, it is worth mentioning the GRY / G16E-GTS is raced competively in several series overseas with no issues of mass oil starvation / engine failure.

 

Feel free to share this information - but please cite us (555 Engineering) as the source so we can continue providing the community this level of R&D data.

 

Disclaimer: YMMV, we publish this data for your convenience.