Quote:

If you run the car at all in cool weather or on the street I would leave it open. Cars run better warmer then too cold



True, but only if you have a functioning heat riser on one side to force the exhaust to pass thru. Otherwise it doesn't do its job correctly.

If you don't have the riser, then I'd guess that it won't warm up much faster than with it blocked.

2017 Contusion Blue Challenger T/A 392 M6 "BLKNBLU"