OVERKILL
$100 Site Donor 2021
Well, he IS racing, and I'd defer to GM's advice on this, given they manufacture the product and in the last few years their approach has been to recommend a much heavier lubricant under those operating conditions. Ergo, I don't find it inappropriate to use the 0w-40 in the OP's case, and I recall being one of the people who recommended it to him, in fact that was the case in this very thread back in 2015:
Mobil 1 0w-40 recommendation
Knowing that this very oil (M1 0w-40) was the standard product for his car in other locations further reinforces the logic of continuing on with it.
Mobil 1 0w-40 recommendation
Knowing that this very oil (M1 0w-40) was the standard product for his car in other locations further reinforces the logic of continuing on with it.