I was unaware that dishing was the main way of lowering compression in place of reducing total height. If so, then it sounds reasonable. However, going from 10.5 compression to 8.0 compression seems a big jump for dishing alone. Plus, if the compression was raised by the heads, and FI was to also be used, then even further reduction of compression would be needed... and I think overall reduction of piston height would be used in such a set up. This is assuming that the heads have an advantage beyond the higher compression.

 

Aren't you supposed to use high octane on our stock motor anyway? If your not using FI than go as high as you can in compression as long as you can still use pump gas 93 octane.

 

with these heads, 93 octane should be ok. Even 91 would do. Stock, high octane is 'recomended for max. performance.' Very high compression would NOT be compatible with 93 octane. I would assume that a tuned VQ35 could run on pump gas at a max of about 12.2:1. That is a none expert OPINION.