I have a regular cab dually with a steel flatbed and was wondering do the extra two tires help with traction and help your E.T. or does the extra wieght slow you down?

A dually will be slower, hp for hp, and lb, for lb. But that doesn't mean it will be slow. The steel flat bed you have will most likely slow you down, due to the added weight of it. It seams that the Turbo diesel racers tend to agree that for every 250-300 lbs you add, or take away, will make about 1/10 of a second difference. (Dual wheels add about 175-225 lbs, depending on size, and type!) Your bed, and training wheels will slow you down a lot. (Maybe a full second in the 1/4 mile!)

On the other hand, a dually 4x2 will get better traction then a singles on a 4x2!