Working thermostatic flapper gave noticeably improved warm up times during TN winters back in the day. Which were kinda like springtime in MI. With the 216 I needed every advantage I could get.
Matthew 6:33
1952 Chevy 1/2-ton 3100 Late '55 235/SM420/torque tube 3.55 Dalton Highway survivor (using original 216) www.truckwithaheart.com
