Overheating on run stand

Thanks guys, no idea on ring gaps, they are within specs tho. Rpm was 2-2800
Yeah the fan in video is pretty lousy but when we broke in the 273 the rad was "good enough". Same rad too.
oldkimmer said
What rpm r u running it at? I usually do 3G but I had the same problem on 1 motor so I slowed it down to 2g and she was a lot better. What r ur ring end gaps? Kim
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Bennoel 10 said
Place a large box fan on high speed directly in front of the radiator to simulate driving down the road. The smallish fan in the video is at an angle and not only too small but only used for a short period. The fan blade on the water pump is only sufficient at idle speed when stopped. Just my observation.
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