What you most likely have is a 2.84 Ratio... You can go as high as a 3.33 but I strongly recommend that if you want a performance minded ratio go with the 3.06, the 3.33 is overkill for a 3800 Tuned Port and will run the motor out of its Torque curve and HP curve too quick, the 3.06 would be a good balance...
also you can have them use the 3.33 Ratio and overdrive it to be a 2.97 if thats what you wish....