My 02 Gt is tuned to take a min of 91 octane. I dont know wtf is going on in our area but every gas station i have been to (10 so far) is out of 89 and 93 octanes. All they have is 87. Hopefully this is a temporary thing, but incase it takes a while to re supply, if I put in 87 and then dump in a bottle of octane boost, would that be a good substitute for 93 octane? Will the overall octane of that tank be bumped up to at least 91 octane? Thanks.