Remember a cold enging generates more HP, but how is your
oil pressure? Mobil 15-50 gets pretty thick at those temps. I have a BB 429SCJ that runs a 180 thermostat and I need to block off my
oil cooler duct because the
oil gets too cold, even in AZ. I also run Mobil 15-50 for track events and on the street I see a 5 to 15 psi increase in oil pressure at cruzing speeds because of oil temp. You might want to change oil to a more friendly version for cold weather unless you plan on tearing up the track on the weekends.....
Keep it above 100.........
Brian