94 octane for me since i bought the car new in 2010. I will be running 50/50 water/meth mix for cooling and cleaning.
The oil catch can i will be using is something made by John Powell. I happy that his unit will have a drain tube back into the block so i dont have to drain the [censored] thing.
I am hoping that once i walnut blast the valves, install the oil catch can, install the meth injection kit, and run low ash oil it will help prevent this from happening again. It is a known issue with GM and i have had friends have their motor blow up due to the carbon build up.