Average Safe Boost level for a LA eng

Granted it is a big block but he was over 9 to 1, used meth injection and ran a truck load of boost....
[ame="http://www.youtube.com/watch?v=oRBC7cZ-JiU"]Matts turbo dart - YouTube[/ame]
Will look for the emails with the specifics.....
He said it used to be 7.7:1. Upped it to 9:1 and it makes more hp/torque per pound of boost than at the lower compression, and as long as the tune is right it runs on pump gas with water/meth injection, no intercooler necessary.....