Sorta backwards thinking here in a way (and I'm not speaking to anyone in particular, so no one take offense, please): Understand that the only reason these high CR pistons are needed at all was that larger and larger cams are used to get more and more HP on the strip. The higher CR is needed to make the engine run with any torque at all at lower and mid RPM's. When the cam selection is being made to suit the application, then the static CR is picked to make it run at idle and lower RPM's in combination with fuel type to help the engine run without detonation.
So IDK.... 'better than 8 mpg' can still mean a pretty darned big cam, and that fits with the high CR. Whether or not the decision to use special fuels will be regretted is TBD. But all this need for a pretty darned big cam is getting further and further away from 'street'. Yes, it can be made to work in some fashion, but the 'out of the ordinary' piston selection is driving the engine into one corner of the performance map, with limited options on how it needs to be setup and how it will run.
OP, just understand that most of the comments here against these pistons are sincerely meant to help you avoid a setup that you won't be happy with. The comments would be similar if you showed pistons with a static CR of 7:1.
