91 octane to stop vapor lock?

A lot of this sounds like the problem I just ran in to. First 85 degree day since I owned my slant 6. I thought the electric fuel pump was cutting out, after it stalled out, pump wasn't pumping to start back up.10 minutes later it would start up and run for a while,then stall again, no fuel in the clear filter. What do you guys think, vapor lock?