I will agree with most of what Banshee has stated. Where will I diverge? There are quite a few people running 10.0(closer to stock) compression ratios on today's pump gas. Now I'll concede that the people running these are skilled at tuning their vehicles to ensure they don't have detonation.
Other sources for info includes the tech articles at Pontiac Street Performance.com, among them a great article on compression by Jim Hand.
1968 400 Coupe, verdoro green, black vinyl top, auto 1969 GTO Judge coupe, Carousel Red, manual 1971 Trans Am, cameo white, auto 1970 Buick Skylark Custom Convertible 350-4(driver), Fire Red, white top, auto 1972 Buick GS Stage 1, Royal Blue, black vinyl top, auto
