[The Deuce]

You are starting to use circular logic to get the answer you are looking for. Note, not actual figures for any car I konw of.

Consider this:

At tdc, 87 and 93 octane make 200bhp.

At 5 degrees btdc both make 210bhp.

At 10 degrees btdc both make 215bhp.

At 15 degrees btdc, 87 predetonates and 93 makes 220bhp.

One could say look, I get more bhp (220 v 215) running 93. However you only get such by running in an area not accessable by 87 octane.

Now go with stock intake v. CAI.

At tdc stock 200bhp, CAI 210bhp

At 5 degrees btdc: stock 210bhp, CAI 220bhp.

To determine the actual power benefit of a variable, you can only change one at a time. It's obvious in the example above that a CAI gives you more power than stock, period. It also shows that 93 will give you more flexibility in setting the timing, and thus allowing more power in certain applications. But in and of itself, higher octane does not boost power. It only allows you to do other things that actually make more power. So if the car runs fine on 87, any 'increase' from 93 will be purely placebo effect. You should theoretically notice a decrease in power, all other things being held equal.

Set your timing, and then run the lowest octane gas possible. It will save you money and headaches.