The other major thing that needs to be looked at, is engine compression
ratios. If it is too high, the engine will detonate, and hammer or melt
holes in the pistons, and other important parts. Also, some fuel systems
are
prone to vapor lock.
--
Jim in NC


So, would it be safe to assume that an engine modified to use 87 octane auto
fuel would not run well on Aviation fuel?
What would you do if your auto fueled airplane was at an airport without
access to auto fuel?