Re: How Hot Is Too Hot?
Is it possible that you header's were radiating heat to the sensor below? I couldn't tell from your second picture if the headers and collectors were in place. Mechanical temp lines also can be affected by running too close to heat sources.
Regarding the 220 temp. That is a great temp. I use 250 as a top with mineral based oils and 300 with racing synthetics.
Alfa Romeo GTV
Don't have my GTD40 anymore