Originally Posted By: bmrlvr
Hallett Motor Racing Circuit--about 40 miles west of Tulsa
The 1,000 mile break-in period is specified in the owner's manual, although I've heard that owner's manuals in other countries for the same car call for 1,000 km, which is only about 620 miles for their break-in period. You're right about not wanting to put in an oil cooler for warranty purposes. Besides, it's going to be the 16th of November and the ambient temperature is likely to be 50 degrees F. It should be ok but I think I'd feel better upgrading to a 5w30 or 0w40 oil for the day. Then I'll put the 0w-20 back in.
The following couple of thread on tracking BRZ and FR-S may be of interest using 0W-20:
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3209489/Re:_2013_BRZ_-_Two_UOAs_%28GC0w3#Post3209489
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3151637/1
For the same reasons it's not necessary to run anything heavier that the spec' 5W-20 in Mustang GT when tracked, (the electronic safeties will kick in if the oil gets too hot), that also happens with the BRZ and FR-S.
The excellent UOA sited above was with the Sustina 0W-20 in a FR-S with Florida track temp's of 275F IIRC. The same member mentioned that oil temp's are higher when 5W-30 grade oils have been used in tracked Toyota 86s vs 0W-20.
If your anticipated ambient temp's won't get much over 50F I'd be surprised if you're oil temp's get much over 235F or so.
Nevertheless, if you still feel the need to run something heavier I'd suggest just substituting a quart or two of M1 0W-40 in place of TGMO 0W-20 to make a heavier 0W-20 or light 0W-30. This is the only way to maximize the HTHSV without unduly raising your viscosity on start-up and during warm-up. In fact this blend is still lighter than all 5W-20s and OTC 0W-20s on start-up.