Yup... ECT sensors are notorious for being off.. And with all the Chinese sensors these days it's only gotten worse..
ive had my MSD Atomic on for some years and i did notice increase in reported temps on handheld compared to aftermarket analog gauge. i was thinking of installing a radiator hose temp bung to hook up the analog gauge again and compare the two
might toss in another sensor and see what happens.
watermelon