X2 on VP octanium or Torco Accelerator. We pack this in the jet boats for long trips where prem isn't readily available and have never had any issues.
16oz will turn 40L of 87oct into 92 oct.
also ran it in my freeride up in candle lake a couple years ago when the gas station ran out of prem on Friday night, put on over 250km
on regular with torco accelerator blended in.
I am becoming a dealer for a fairly interesting additive called Shellbourne Fuels, I will be trying it in my turbo shortly and posting results. It will be the same price or less than av gas but way more convienient and it is supposed to have excellent gains and work well with mixing premium which I am pretty pumped about. My first case just showed up and I will be trying it on the next trip and I will be running 9 pds boost so it should be a great test.