So, I like to read outdated How-To books and, a long time ago, I read in one entitled "How to Drive Sports Cars" --or something like that-- that a sports car should have at least 250 horsepower. That was an enormous leap from the cars I was familiar with as a 10-year old kid in the 1980's, and that number stuck with me, even though later I would learn that 250hp means different things in different situations.
Later, I got enamored with other ratios, power density figures and power to weight ratios like the 10:1 lbs/hp. These are all a bit arbitrary, but then, any number you attach to a concrete phenomenon is bound to be so. Regardless, those two stuck with me, 250 horsepower and 10:1 lbs/hp (which consequently works out to around 280 for my car). Therefore, that became my goal; to achieve between 250 and 280 horsepower in a street-friendly (note I didn't say "streetable" because that can be interpreted more loosely), naturally aspirated engine.
Here's where we're starting. The baseline for power is measured on a chassis dyno. My goals are as they would be measured on an engine dyno, so we will assume (arbitrarily) that the chassis dyno costs about 25 hp or 15%. The difference is negligible considering the relatively low horsepower numbers and the breadth of my target hp range. That means I'm shooting for somewhere between 213 and 238 horsepower on the chassis dyno. Note that I'm not especially concerned about torque numbers, so long as they don't go down.
