Jim, I'd suggest you do further research into octane and what it means.

octane (ŏk'tān') Pronunciation Key
Any of several hydrocarbons having eight carbon atoms connected by single bonds. It is commonly added to gasoline to prevent knocking from uneven burning of fuel in internal-combustion engines. Octane is the eighth member of the alkane series. Chemical formula: C8H18. Source: "octane." The American Heritage® Science Dictionary. Houghton Mifflin Company. 08 Jun. 2007. <Dictionary.com http://dictionary.reference.com/browse/octane>.

Other hydrocarbons are more suited for creating power. Octane itself DOES NOT MAKE EXTRA POWER, it simply allows for more power to be made at a given cylinder pressure.

And seeing Brent's skills firsthand I have no doubt that he could tune Doug's car to run well on 89 octane.