[Brian Baker]

What Skip said.

You've got 3 things here that need to be addressed to get that car to run where you want.

More timing. I would start at 32 total and bump it 2 degrees advanced from there until the car slows, then turn it back. In other words, set it to 32 and make a pass, set it to 34 and make another pass. Don't look at the ET, look at the MPH. Keep advancing 2 degrees at a time until the MPH drops off, then reset to total timing mark that produced the fastest MPH. Don't make any other changes while doing this!

Better tires. You're not going to get any grip at all unless you run a slick, or one of the DOT rated "stickies" (like the Mickey Thompson ET Street or the BFG drag radial).

Less gear. That 3.73 is just too much gear for a mild 455. 455's tpyically produce broad, flat torque curves, so it's best to load the engine down and take advantage of this. If you stick with a 28" tall tire, I'd drop the gear to at least a 3.55. 26" I'd go with a 3.23.

Additionally, after sorting all of this out, try different shift points. You may find that it runs quicker when shifting at 4800-5000 than shifting at 5400-5500.