360 to a 408 how much quicker

I think it's going to depend on the carb tune and the traction. If the carb is tune real good (remember, you're feeding alot more cubes now so your probably gonna have to change something)and the car hooks up real well ( you should have a bunch more torque)you should pick up quite a bit. How much we'll have to wait and see! Good Luck and tune'r up!