As I look at this further, the Spot Trace seems to be promising.  It has a movement alert system and will notify you in the case your car is moved or if the device is powered off.  $119 plus $100 per year service.  Reviews aren't bad either..  Amazon.com

This was an interesting review on the device

"SPOT Trace led me to believe that my boat would be safe using this device and their service. Truth is the day my $233,000 boat was stolen it didn't do a thing. Why? Because these SPOT Trace devices can be easily found due to the fact that they emit an RF frequency to communicate with GPS satellites. Anyone can buy an RF detector here on Amazon that will tell a thief if your boat, motorcycle or car has one. They simply find the hidden device, turn the device off or remove the batteries and your car boat, truck, or motorcycle disappears! When we told the police officer taking the report we had satellite tracking on the boat he said those are worthless. A thief who knows his trade will not let a tracking device like SPOT Trace get in his way. SPOT won't tell you this. They lead you to believe your vehicle is protected. That's not always the case. SPOT Trace is no deterrent for a professional thief!"

I wonder if a phone or Lojack concealed in the car gives off a similar RF signal...

5 hours ago, Patcon said:

This was an interesting review on the device

"SPOT Trace led me to believe that my boat would be safe using this device and their service. Truth is the day my $233,000 boat was stolen it didn't do a thing. Why? Because these SPOT Trace devices can be easily found due to the fact that they emit an RF frequency to communicate with GPS satellites. Anyone can buy an RF detector here on Amazon that will tell a thief if your boat, motorcycle or car has one. They simply find the hidden device, turn the device off or remove the batteries and your car boat, truck, or motorcycle disappears! When we told the police officer taking the report we had satellite tracking on the boat he said those are worthless. A thief who knows his trade will not let a tracking device like SPOT Trace get in his way. SPOT won't tell you this. They lead you to believe your vehicle is protected. That's not always the case. SPOT Trace is no deterrent for a professional thief!"

But the device is easier to get at inside a boat right?  whereas in a car they have to get inside without setting off the car alarm and then there are lots of places behind door panels, interior panels to hide the device.

There are lots of video's on youtube where people have tracked their stolen cars and have brought police to that location to recover it.  Our old datsun's hopefully will never attract this caliber of thief.

 

1 minute ago, hr369 said:

But the device is easier to get at inside a boat right?  whereas in a car they have to get inside without setting off the car alarm and then there are lots of places behind door panels, interior panels to hide the device.

There are lots of video's on youtube where people have tracked their stolen cars and have brought police to that location to recover it.  Our old datsun's hopefully will never attract this caliber of thief

This is true! Although I would think a $233k boat has a locked area at least as secure as a Z...

although nice Datsun's are now trading at $25k, in 7 years they will be pushing double that if things don't change. I would think easily stolen, $50k cars would be appealing to someone who has a way to ship them overseas...

bad news. they can just tape a rf signal jammer to the side of your car and drive off into the night. crap.

The good new is you can buy a $30 jammer to plug into a cigarette lighter when you rent a car and sometimes go off-roading or very fast.  They won't know a thing.

I'm not sure all criminals would be that smart.  But, anything is possible I guess.  However, getting back to the original title of this thread... theft prevention.  A GPS device would likely be considered theft recovery.

To prevent a theft, I typically remove the coil wire and take it with me.  A more sophisticated solution would be to install a keyed ignition shutoff and alarm.  When I was younger I used "The Club" but that can easily be removed.  The best way, IMHO, is to set it up so the thief cannot start the car.  But, then again anything is possible if a thief really wants your car.  Maybe we should rename this thread to "Theft Deterrent"...

I just ran across a cool device put together by a fellow Datsun fanatic.  @ron carter is the sales director for this company that provides a GPS tracking system for classic cars.  Check it out!

http://www.geoskyalert.com/

That looks like a pretty good system

On 8/21/2016 at 11:14 PM, Mike said:

I'm not sure all criminals would be that smart.  But, anything is possible I guess.  However, getting back to the original title of this thread... theft prevention.  A GPS device would likely be considered theft recovery.

To prevent a theft, I typically remove the coil wire and take it with me.  A more sophisticated solution would be to install a keyed ignition shutoff and alarm.  When I was younger I used "The Club" but that can easily be removed.  The best way, IMHO, is to set it up so the thief cannot start the car.  But, then again anything is possible if a thief really wants your car.  Maybe we should rename this thread to "Theft Deterrent"...

My philosophy is along similar lines. I remove the rotor from the distributor. With the coil wire, someone could possibly use one of the spark plug wires and drive off on 5 cylinders. If they have a spare rotor with them, they are determined to drive off in my car. 

Of course, anymore a manual transmission is somewhat a theft deterrent.