20psi on the vf52 is too much without supporting mods. You would have to retard your timing so much all you would be doing is putting un due stress on your internals and gaskets, you won't gain power. Charge would be scolding hot and would knock like crazy with the stock intercooler, not to mention the 11's intercooler would blow apart in about 20 miles or less with that kind of pressure, unless you are lucky. 20psi is ok on the VF52 at "peak", it won't flow hard enough to push more than about 16 past 5500, well maybe at sea level. Still bottom line, trying to just "push 20lbs" is a very bad idea. Like the above posts state, there are way too many variables to even consider pumping the boost up until you have a very good idea about what you are doing. The stock AFR levels are wack for emissions reasons, spool up timing is somewhat retarded, and the stock 2 port boost controller is very hard to dial spike out of and still reach early boost. Just way too many things happening for people to blindly turn up boost, but they still do it.... and we see em back asking "what that sound is"