As rule of thumb its my understanding that from 91 to 93 is a approximatley a 7hp gain. Same like going from 89 to 91. There is always variables i guess like anything else. I got 7hp going from 91 to 93 but it was all above 5500 and with a much leaner tune. So I guess you could argue it wasnt all from the octane jump. Could be close to a 1/10 in the 1/4just wondering someone told me there could be up to 10hp going to the 93 tune. sounded a little much to me so I thought i would ask. I can not get 93 at the pump where i live so would just running race gas 110 octane be fine with my tune.