How much horsepower is produced by a NASCAR racing engine?
With unrestricted motors: Previous to the 9500 RPM rev limit rule, NASCAR Nextel Cup engines were producing close to 900 flywheel horsepower. This is when they were spinning up to 10,100 RPMs. Of course, the best teams were making this horsepower, and the independent/small teams were a bit behind. Here is an approximation of horsepower numbers produced over the years: 2004: 875 (or more) fwhp 2003: 840 fwhp / 750 rwhp 2002: 825 fwhp / 735 rwhp 1998: 750 rwhp / 680 rwhp All of this data is based on post-race dyno testing posted on jayski.com. All of the teams tend to underestimate and keep their real horsepower numbers a secret (which is why most sites tend to say no more than 800 horsepower). With restricted motors: 420-450 flywheel horsepower, depending on the size of the restrictor plate.
