Thanks for the reference on improvedracing.com, I am also looking to install an
oil thermostat. I am not sure what the pros/cons are, but with the sandwich type ENV-131 unit, the
oil does not flow through the filter until after it has flowed through the
oil cooler (when the thermostat allows it), while with the remote mount ENV-170 unit, the oil always goes through the filter first. Attached are the flow diagrams when the oil is hot enough to open the thermostat.