Originally Posted by InfiniteVTec
My car is N/A with many upgrades, it runs best on unleaded plus... which is 89 octane gives me the best Power and fuel economy.. If I use 87 octane, it gives me poor performance good econ, and with premium 91octane, good performance poor fuel econ. Hopefully my VAFC2 will give me even better power n fuel econ.
As for the idling issue, seems like a vacuum or Intake Manifold leak.
That was really pertaining to a unmodified civic. Boosted or N/A w/ block or headwork is a different story.