Everything NB said.
And, you could lose some weight. If you really want to pull, that is. Spare tire, any gas over 5 gallons, carpet, pad, trim, blower motor, heater core, air conditioner, spare seat. You see what I'm talking about. Shed 200 pounds and your car will come alive.
You say you have a 83, so you probably already have the 3.9 rear end. If your car was a turbo, I think it has a 3.7. There are taller ratio rear ends (4.1, 4.3), but they aren't common, and they are expensive.
Practice your shifting under load. You may not be using your HP effectively. Keep in mind where your car developes the most power, and try to keep your shifting close to those limits. A lot can be gained just by improving the driver.
Our cars are not good dragsters, generally. Challenge someone to some twisties, and watch em squirm.