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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>For an Austin-Healey the main purpose of the thermostat is to help the engine warm up faster by staying closed and allowing the coolant to reach a higher temperature faster. That said, the thermostat will gradually open as the coolant reaches the thermostats full open temperature. So, if you drive in a colder climate, you might want a thermostat with a higher opening temperature, say 180, in a warmer climate you might want the 160 or 165. I think I have a 160 in my car and it is fully warmed up and running without the choke engaged when the temperature gauge reads 190.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>John Spaur<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>’62 BT7<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Healeys <healeys-bounces@autox.team.net> <b>On Behalf Of </b>Richard Antal via Healeys<br><b>Sent:</b> Wednesday, September 17, 2025 11:33 AM<br><b>To:</b> Healeys <a href="mailto:healeys@autox.team.net">healeys@autox.team.net</a>s<br><b>Subject:</b> [Healeys] radiator thermostat<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif'>Gents,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif'> What is the desired coolant temperature for optimal engine performance? I've searched the tech articles and can find nothing that specifically answers that question. This summer my BJ8 seemed to run fine with a 160 thermostat which, according to the gauge which I've checked and found to be accurate, kept the coolant at around 165. Thanks to all who respond.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif'>rich antal<o:p></o:p></span></p></div></div></div></body></html>