Nicks Garage 383 build

That's very true. With chassis dynos as well. Did they include which corrections and such they used? That can have a huge impact as well. The only hands on dyno experience I have is decades old back in school when our auto shop class was able to use the dyno at Mercer University in Macon. After that, since we were "kinda somebody" and knew those at the school in charge, we were able to dyno several of our own engines while learning a little something, even though were were not enrolled at Mercer. There are SO many variables that you can take a 250HP engine and make it seem as if it produces 500HP. I guess what I'm trying to say in a nutshell is, you need to KNOW what you are doing to operate a dyno correctly.

The only way that can happen is if the dyno operator is an idiot or a liar.

If you are using the same correction factor (and is should be STP and not the newer factors) there shouldn’t be 10 hp difference from corner to corner of the country.