i have 430s, my engine is stock an my car hauls ass,(for being almost all stock) you shouldnt run out of gear, you will cross the line in 4th depending on where you shift your car. they deffinatly make a huge difference over 373s, with just gears my car can hang with some heads, cam, an intake cars. nothing crazy though. for example a friend of mine has a 5.0 with a B cam,gt 40 heads, gt 40 intake, 355 gears, full exhaust and 24lb injectors an he beats me by one car, i take him the whole race an just at the end he will pull on me an ill be at his bumper, for a car with just 430s, and exhaust that is pretty good imo. from having 430s i can see you possibly taking about a second off your quarter mile time with them