Online Horsepower Calculators

Hmmm... I always figured they told you RWHP. Example: If a car has 1000 hp at the flywheel, but it has traction issues and runs a 10 flat. The calculators will take the weight, ET and/or MPH and come up with a HP needed to move that weight for that distance. The flywheel HP is irrelevant. What the track sees is RWHP. We have all seen just the opposite occur - a 400 flywheel HP car lay down extraordinary numbers for that HP. The track doesn't have any idea what the flywheel HP is, only what HP the rubber puts into the track. The reason I say this is because those online calculators use the numbers generated by runs down the track to compute the HP. As already stated above, they are only a guide. I will use my Cuda as another example. I know what the engine HP is because we dynoed it prior to installation in the car. I made some track runs and then plugged the numbers into the calculators and they came up about 100 HP shy of what the engine dynoed.