OLD Galion 503 in Projects, Builds, & Restorations Posted January 5, 2017 I got that Block Heater thanks to Rainman and Farmallfan. It was simple to install. I just wanted you guys to know what my tests did. >> After install I thought it best to see the performance of this heater. I had 22 degrees outside. Inside I used a heat gun probe Before i plugged in it was 34 degrees. In one hour it was 64 at the block and head. I tested the next hour and it was 81. The next hour it was 94. I suspect 3 hours are best if you have a timer. The fourth hour was 96. ,,, not much gain.. Hey AKwelder,, send snow down please.