What you posted was likely what's called "advertised" duration...
But we all want is the best of both worlds where it idols nice and smooth but has power like a dragster...
Also keeping in mind that Dinos are just a tool for tuning... Dinos can be different from each other but the thing they have in common is they give you a baseline reading and then you can improve from that baseline or unimprove through adjustments... The chassis Dyno like you have gives pretty much a baseline with your whole combination of transmission gears rear end gears but still doesn't take an account for the weight of the car...
An engine dyno just gets the engine and it's best performance..
That's why nothing beats a real world test like taking it to the track and getting a time slip... That's where it counts anyways... You try tuning the carburetor a little bit and get another time slip dry some different timing and get another time slip....