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How to choose the best fuel

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I run a 557 Ci BBF. It is around 14.5-1 Compression. This past year we ran Q-16 my question, however, is would I be better with a fuel that has a higher octane rating? As opposed to the oxygen content? I have heard both ways some people state that Q-16 with a high oxygen rating however some have also stated that my application would be better with higher octane or maybe even something else. How do I decide this, How do I know what is better? Is there any advice here you can give me?

-Note I cannot run Alcohol and we run 250 feet double elimination.

This is the type of question that is answered with the dyno where you can measure the results of a change. If you are currently knock limited, then perhaps using a higher octane would revel more power with proper ignition timing.

Make a test plan:

-- Make sure the conditions (engine temp, oil temp, etc) are as close as possible as you do your testing. It's easy to get fooled as the oil temp rises and the power just keeps going up. I suggest using targets that are a little high, and warm the engine / oil up to this before the start of each run. If things are hot, you will just have to cool them (wait, idle with fans running, etc) until you can have close to the same conditions for every run.

-- How are you going to change fuel (one fuel in your existing cell / tank), and then change the plumbing so that it draws straight from a fuel jug (my preferred way to test fuels)? Or will you pump out the existing cell, and refill with different fuel (hard to get all the old fuel out, so you have to more of the second fuel to minimize any leftover fuel.

-- How are you going to check for knock?

-- Are you going to change mixture targets with each fuel and re-tune the ignition to make sure you've really found the maximum power. What are the Lambda/AFR targets to try. How many runs will use use to verify the ignition timing. Make sure you have enough fuel for all this testing.