hello there from australia
i have been doing some research and noticed in the early seventies the GTO nicknamed the Humbler (I tihnk)had an adjustable exhaust valve and i am wondering if anyone knows where i can get my hands on a exhaust valve setup off the old GTOs if anyone in the states has what im after let me know ASAP
thank u

You probably are talking about the VOE -Vacuum Operated Exhaust. This system used a vacuum switch to operate exhaust cutouts. There was a switch on the dash to operate the VOE. Very desirable option and probably pretty expensive if you find one. I've only seen a couple of GTOs with them.

The nickname "The Humbler" came from an ad campaign Pontiac ran for the 1970 GTO. I have the ad around the house somewhere, if I find it I'll try to post it here. As I recall the tag line at the end of the ad was "Any Questions?" They had some pretty clever ads back in the day.