A prostocker would not stop at 20hp gain. They constantly look for more like all other racers. I have test and tuned at the track a bunch gaining some mph, but not much in et. I stand by what I said earlier, it takes a lot of power to see anything on your et slip and the faster you are all the more it takes to go faster yet. With a car that 60's exceptionally well you may see more gain with 20hp. My car best 60's were 1.45, so et gains come slow in my program. That plastic fan has a few stories written about it as being the worst out there for costing hp. One of the reasons people use electric fans, free up power. If your not chasing et's and it cools good, i'd run it, who cares.