Spal 30102038 12-Inch High-Performance Puller Fan Paddle Blade - 1640 CFM Cooling Fan (1 Pack) | Perfect for Automotive Radiators, Cooling Systems & Industrial Applications

Let me start by saying I don't write many reviews but thought this might help someone else. I have a very modified Big Block Oldsmobile in a 1970 Cutlass. It's a stroked 455 (now 488) cubic in motor with aluminum heads, big cam, etc.. etc. I'm guessing 500 plus horse power. When I installed the motor I also purchased a 4 core aluminum radiator package that included 2 12" electric fans. Won't give the brand name, but ordered it here on Amazon and I'm guessing it came from oversees. Actually the Radiator looks OK, welds are good, etc. However, the car ran hot in the 220 range no matter if if was at idle or running down the road. The temp would just continue to creep up until I would have to shut it off and let it cool. The motor was completely rebuilt, hot tanked and checked so I didn't think the passages would be clogged, so I made sure the tune was good (timing, carb) and than switched to a better performing water pump. The radiator did come with a nice shroud. Although these changes helped a little, the car still ran hot and over time would clime to 220 or more, before I would shut it down. The fans that came with the kit ran off of a single 30 amp relay and they kicked on at 185 degrees. The fans that came with the kit seems to be flowing a good amount of air. Although I have no way of measuring other than putting my hand behind them.After doing some research, I decided to change fans and give these a try. I did have to buy another 30 amp relay to run each fan on their own 30 amp relay. That was already a good indication that these fans would be more powerful and move more air. I also found out that the fans in the kit stated 12" but the fan itself was actually about 11" and the shroud was 12. On these fans, the fan is 12" and the fan shroud was about 13". I ended up cutting and opening up the holes on the metal "electric fan mounting shroud plate" that came with the other kit to accommodate the 12" new fan opening. Had the room, it was no big deal.Took the car for a test drive in the middle of the afternoon when the temp outside was about 92 degrees. Relatively hot day where I live in Colorado. As soon as the temp got to 185 (I have a set of really good gauges that I trust) both fans kicked on. At no point in time after those fans kicked on did the temp go over 180 degrees on the guage. I sat in traffic at idle, ran the car hard down the freeway, around town, etc. Never could get the temp above 185 on the guage. With the other fans, I would shut the car off when the temps were high and you couldn't touch the engine, radiator or radiator hoses without burning yourself. Now you can put your hand on a valve cover. Yes it's hot, but not nearly like it was before.I just thought some other "car guy" might find this review helpful. At times you try to resolve things and sometimes it works and other times not so much. I was so happy with these fans as they fixed the issue I was having. They didn't make it a little better... they completely solved the overheating problem I was having!