To dyno or not to dyno?

Mattax said

Running the engine on a stand takes care of initial break-in and any concerns about issues - if the price is reasonable.
Utility of the chassis dyno depends heavily on the operator or you, and what you want to get out of it. For full power mid to top end an inertia dyno will show which changes add or subract more Hp for each change. If its got WBO2 tail sniffer you can also see if the AFR is drifting during the pull and things like that.

That said, the mph in the 1/4 will get you pretty close, usually for less money, but depending on how busy the track is, may take longer, and even repeated visits. Plus you get to run the 1/4 mile. :)

For cruising and throttle response you'll need an eddy-current dyno and an operator that knows how to work it for those things. That's a rarity. Expect to do the street tuning on your own.

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An engine run-in stand is not the greatest solution either. You cannot put any load on the rings just running in essentially neutral. The SF-902 has an automated test cycle literally called "break-in". I use it all the time. I have never seen anyone on YouTube ever use it or even knows about it. It works like this:
The operator selects the lowest rpm the engine will see I usually select 1900rpm, and the the highest rpm which I like 2400rpm. Then number of seconds per cycle, I like 60 to represent minutes and then I select 5 cycles = 5 minutes. I start the engine hit the start test button and then put about 75-100 ft/lbs of load on the engine. The test cycle will spend 30 seconds dragging the engine down to 1900rpm and 30 seconds reducing load to allow the engine to hit 2400rpm. I leave the console and check timing, water, exhaust temp etc.....After 5 cycles I shut it off for 5 minutes and then repeat all over again for 3 more cycles for 20 minutes total. This loads the rings properly, and I can usually tell if other issues will arise during this process. FWIW, J.Rob