I have two 520s , I have installed the new maps 937.5945 with Navcore 9.701 on one and my other 520 has Truck map 900.4612 with Navcore 8.398 , now if I put same route in of approx 150 miles the new maps and Navcore are adding 30 minutes on to the time I know this route will take , the older maps and Navcore are spot on with time .
Is there any particular reason for this ?