LouisianaGuy, if you want to make best use of the cam you have I would use a 3.08 or 3.23 gear at the most, 3.08s being the better choice. You probably can't use a tall enough tire to drop the 3.73 gear ratio you now have into the best range for that mild cam. A 29.5" tall slick is about the tallest you can fit on your car with cutting up the wheelwells. Any street tire on the rear that tall won't provide any kind of decent handling that the T/A is famous for for everyday driving.
Even if you swap to the RAIV cam like Brian suggested a 3.23 gear would be ideal with a 275/60-15 tire that is about 27 to 28" tall. My own set of 275-60-15s measure 27.25" tall, not even close to the 30" dimension that you have stated. The 3.73 gear and 29.5 tire would be ideal for a mid-11 second 455 powered race car with a very large cam. 3.73s are too much gear for a street 455.
I run a similar cam (factory 068 w/1.65 rockers, 212/
[email protected],.447" lift) to the one you have in my own very mild 455 powered daily driver. Here are the rest of the engine and car specs:
www.outlawpontiacs.com/members/B-Man.php As you can see my car runs a 2.56 gear (no posi, so I have to roll on the throttle gently) and a 25.25" tall 235/45-17 street radial. I recently swapped the 2.56 rear for a 2.93. It ran just as good if not better with a 2.56 gear than with the 2.93s due to the very mild cam I selected. It ran a best of
[email protected] at a sea-level track with the 2.56 gears, ran a 14.1@100 with the 2.93s. Different tracks for those runs, but similar elevations and weather conditions. My 60' times were 2.2 to 2.3 seconds.
455 engines like tall gears, don't gear your Pontiac like you would a Chevy!
Good luck.