Others have mentioned advancing the cam or timing curve & Im sure that needs to be checked... but on an old 455 6X-4 heads ~9-9.5:1 comp I had in the 90's on a very tight budget build with a mild comp magnum 280 cam and cheap 2300ish converter... that cam was installed straight up due to lack of experience using a stock timing curve HEI... that car would smolder the tires off the line even with 2.56 gears & a TH400, I changed to 3.73 gears & you could barely do half throttle launches without the tires going up in smoke. Even a totally stock 455 has more than enough low end torque to smoke the tires at will from a stop.
I also have a 400 9:1 in a 78 TA with smaller comp XE cam that I installed straight up and using stock timing curve, that car also smokes the tires easily with 3.42 gears and runs mid 13's at 103+mph taking it easy on crappy hard street tires.
Many of todays modern cars, even V6 smaller cars feel super quick from a stop or 25-30mph roll, but that can be deceiving compared to a big heavy car with a slower revving big V8. Hope you can figure out the issue with some of the suggestions above, but dont throw a bunch of money at it from a shop that charges 100+/hour labor, if you have basic tools & mechanical ability you can check or do most the things yourself with some help here or other interweb sources.
Maybe consider a shop with a wheel dyno that can do some tuning or changes without getting inside the engine for cam work etc?
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