What octane should I need?

If you scroll down the article RRR posted there's an interesting "reply" someone posted regarding Toluene. According to that you can get toluene at paint stores for pretty cheap and it's an effective octane booster (much more than the bottles of stuff at the auto parts store) which you just mix in with pump gas. Apparently it's also the main ingredient that makes race gas (unleaded) have higher octane.