Gernby

Most of the mods that I have done are intended to decrease the air intake temperature and engine temperature. I have an AEM CAI with an insulation sleeve over it, Hondata spacer / gasket, and Mugen Thermostat / Thermoswitch / Radiator Cap. These mods may or may not make the engine run cooler (or even hotter). I went to a colder spark plug (Denso Iridium IK24), and they are doing great, which I think means that the OEM plugs were too hot.

To make the cooling system more efficient, I have also increased the ratio of distilled water in my coolant to about 75% instead of the normal 50%, and added Redline Water Wetter. These changes will probably make the engine run cooler by improving the heat transfer into the coolant, which could make the temperature of the coolant hotter. Because of this, I don't think that measuring the coolant temperature via OBD-II would be particularly helpful.

Do any of you have any suggestions for measuring the temperature of the engine / head / oil? Are there any OBD-II sensors that report this to the ECU? I know that I can install an aftermarket oil temp sensor / guage, but once I determine that everything is right, I am not going to want to look at it anymore.