A first generation Nova with the Sky Drive unit installed under the dash.

A recent craze that’s swept through the classic and custom car community is the advent of the GPS speedometer. A GPS controlled speedometer allows you to get accurate speed with minimal work involved in set up and they are able to work in cars where a traditional cable-driven speedometer would not be a feasible option. The only problem, and this is a big one, is that you’re limited to the GPS speedometer styles available—or at least you used to be.

With Classic Instruments Sky Drive system, you can turn nearly any electronic speedometer into a GPS speedometer, and installation is a breeze. We were really interested in what you could do with a Sky Drive system in a classic car and wanted to find out more, so we got in touch with John McLeod, owner of classic instruments, and got some more input from the professionals.

“All of the speedometers we’ve sold over the last 40-years can be made into a GPS speedometer with Sky Drive,” John explained. “Some people think that the only way to get a GPS speedometer is to buy a new speedometer, but the Sky Drive system can make your existing electronic speedometer function as a GPS speedometer.”

The ability to make almost any existing electronic speedometer into a GPS speedometer is one of the key factors to what this product can do. If you already love your instruments, but want to change over to a GPS speedometer, you don’t have to give up your current gauges. All you do is install the Sky Drive unit and you’re good to go. You can keep using the same Classic Instruments speedometer that’s been in your car for decades!

We’re not the only ones that think this is a big deal either. In 2011 when this product was first released it won the best new product of the year at both SEMA and NSRA Street Rod Nationals in Louisville, Kentucky. This is an important product because it makes GPS speedometer accuracy and functionality available to any square-wave electronic speedometer.

“Sky Drive is different from other GPS speedometers because it is an added sending unit to an existing electronic speedometer,” John told us. “It works like a pulse generator, ECU, or cable for a cable driven speedometer, it’s the sending unit that make an electronic  speedometer work.” It’s incredibly simple too, you just put the device in your car, wire constant power and ground then  run a wire to the speedometer, connect it to your speedometer, push a button, and you’re done. It can give literally anything that moves a functioning speedometer.

Classic instruments showed off the versatility of the sky Drive system by giving a shopping cart a working speedometer. Take a look at the video below and you’ll see the folks at Classic Instruments testing their GPS speedometer enabled shopping cart. The system has also been used in other ways that might surprise you. For example, Kyle Tucker, owner of Detroit Speed Engineering, uses the Sky Drive system in his trailer so that it has an accurate odometer and he can easily keep track of when it’s ready for maintenance.

There are some distinct advantages beyond accuracy and ease of installation that are offered by Sky Drive that simply can’t be met with the use of a standard cable-driven or electronic speedometer sending unit. “There are certain hotrod transmissions that do not offer the output for a speedometer without a magnetic proximity sensor,” John detailed. “These run off the driveshaft, flywheel, or studs on the wheels. They’re difficult to setup and a lot of work. That’s where you’d want a GPS speedometer.”

Sky Drive also has an optional security feature called Sky Fence. If you’re already using GPS technology for your speedometer, why not apply the global-positioning to a security system as well? “If you activate Sky Fence it will trip a relay when your car moves 100 feet, John said. “That way you can use it as a security device so when activated it can be used to shutoff anything that operates with a relay.” Pretty cool, huh?

We just love the size and simplicity of the Sky Drive system!

We also asked John about the obvious question of accuracy and reliability, and again Sky Drive is a step ahead of some of the other GPS enabled speedometers available on the market. Sky Drive uses an Omnidirectional antenna, as opposed to a standard directional antenna, this means that it can catch signals from all directions. “I’ve been very successful using these even in the long tunnels. Like all GPS units, they are not perfect, but in our testing, we’ll lose cell phone signal and XM radio connections before you lose the Sky Drive,” John told us. “With our omnidirectional antenna, it doesn’t matter if it’s mounted sideways, upside down, or whatever, it will grab any signal it can find and it’s updating ten-times per second, so it’s extremely accurate.”