[ByronRACE]

If it's a known build, then the engine dyno is just a good way to spend money. If it's an unknown build, then you will probably save a bunch of money by hammering out all the experimental qualities of the build in an environment where you have ready access to everything that can go wrong. If any of the seals, freeze plugs, gaskets, heads, cam, etc are in question then by all means break it in on an engine dyno so you can easily remedy those issues and move on. If it's a known build using known parts and just like 100 that have been built before, then I don't see the benefit. I would just break it in on a motor stand. If the motor stand has a brake on the output shaft for applying some load, even better. If not, then don't sweat it, you can apply load as soon as it goes in the car. Just test it for leaks, break the cam in, then install it in the car.

B