Car insurance + 3 points?

heya ok to cut a long story short i got pulled ove by the police the other weekr and i had a really worn out tire on my car.. i got 3 points for it and now 2 weeks later it my insurance renewal i know i have to tell them about the points and thats fine but this is where it gets slightly interesting, my renewal with no points would cost �790 for the year but if i tell them about the points i think it goes up to �1100 so i looked about online i added the points in the quotes and everywere is about �1300 so i was messing about with the insurance options and i changed the price of my car value from �400 to �3000 and i got a quote for �770 i couldnt believe it so i checked over all the details and they are all correct apart from the value of my car so my question is... does it really matter that i put 3000 as the value?