I've just completed installing the LN low temp thermostat & coolant changeout last weekend. My temp guage is metric so I have /80 as opposed to /180 on the display.
Previously the indicator needle lay straight thro the 8, but with the new thermostat it now runs on the left hand side of the 8, slap bang on the / mark.
But the biggest advantage is that the needle stays in this position even when driving in heavy traffic wheras with the original, the needle quickly crept up past the 0 mark of the /80. This leads me to the conclusion that the t/stat is fully opened and is now flowing fluid to the full cooling capacities of the radiators.
As a side note, the old coolant (8 years old with 67,000km or 42,000 miles) was still clear, no scale visible & the inside of the t/stat housing and pipework was perfectly clean too. So maybe the Porsche "lifetime" coolant really is top shelf stuff.....
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