Found this over the holiday weekend last week and forgot to post it. And I gotta tell ya, I'm one of those that just a few weeks ago was a firm believer in dyno's. Since doing the research on the Dynorad and chassis dyno's in general I've done a complete about-face attitude-wise on their credibility, veracity and accuracy. Today I'm suspicious, cynical and frought with doubt about all of them. I can't believe how a simple figure such as mass-factor can be slipped up or down one point or more by the dyno operator to influence/affect/skew the dyno's outcome based on what the tester wants to see. Or worse, what the tester wants the customer to see. Or forgetting to re-set it after the last cars run. Laziness; intentionally leaving it rather than doing the preliminary, pre-requisite set-up work because he couldn't care less. And even complacency... never changing it for any car... leaving all cars to run at the same mass factor.

Anyway, here ya go: Single page document, an easy read and very insightful.<ul><li><a href="http://www.sdsefi.com/techdyno.htm">Link</a></li></ul>