Ive come to find Engine Break in is all in the eye of the beholder. Everyone has a different way , method , process , route etc...in otherwords everyone goes at it in a different way.

Unless someone can proove without a shadow of a doubt their way is better. Then most everyone who gives you advice will be just of opinion nature and not of truthful fact, as there really isnt any.

Allthough a lot of people can agree on certain aspects theres a lot to disagree. I would just say this , try to keep as much fuel (lubrication) going through the engine as possible. Get to 10 tanks and then start leaning it out 1/8th of a turn each half a tank till you get your motor running the way you want powerwise. Then use the temp gauge to monitor and keep it in range. I wouldnt go over 250F in a monster truck , in a touring car 240F id tried to keep it under.

But then there are people who run 270 and say it runs great, just shoot for power when you find the max power , back it off a little (richer) so your right at the peak power but still giving it enough cooling to function properly and keep wear down. Its also good to keep an eye on how much it smokes. If its not smoking , then your probably too lean.

Also yes cooler outside temperature will result in cooler readings. Nitro motors are definently effected by many environmental changes , even beyond temperature.

Happy Tuning.