Newbie looking for some info

Hello all, I'm new to the forum. I've used similar forums for everything from my cars to my pool with wonderful input and results, so I'm hoping the experts here can lead me in the right direction. I live on a residential street that has some serious speed issues. Long story short, I've been working through various city officials to implement some corrective measures, and I'm not getting very far. Problem is that the area of concern is literally a drag strip and all measures the city has used to validate my claim have proven ineffective. They have installed a portable radar trailer (w/ no manned patrol) to show drivers their speed, and after it was removed they sent their Mustang GT patrol car out to write a few tickets. The problem is that on the "Drag Strip" each is as visible as the Christmas Tree light on a real drag strip, identifiable from either end of the strip. Very few in their right mind is going to test either one, particularly with the reputation the officer driving the Mustang has. I've literally watched drivers calibrate their speed with the trailer, and the very same will crawl and some have even stopped to chat with the officer in the Mustang. I have a Nikon D-40, and was wondering if there was a way to use it to validate, to some degree, the number of vehicles that are exceeding the speed limit. I thought there might be some chart or guideline that would allow me to adjust shutter speed producing blurred images for vehicles traveling over a certain speed while producing clear shots of those traveling at the posted or lower speeds. My daughter's vehicle was recently totaled while parked in front of the house, and the vehicle that hit hers literally ended up at my front door (third car in almost as many years in my front yard). Local police department has thrown up their hands, city engineer blowing me off, so I'm close to wits end trying to figure out how to validate the issue. Any direction or suggestions are greatly appreciated.

Interesting problem you have. Sounds like you could use a speed bump in your street.

You can calculate speed with a camera. You'd have to pick a shutter speed slow enough to allow the car to blur and then calculate speed based on the amount of movement and your shutter speed. You'd have to use a tripod for your results to be consistent and reliable.