How a sat-nav can make you faster around a track

There’s no connection between the device and the car’s ECU, though, so we get no data on throttle position, engine revs, steering angle or braking forces.

The idea is that we drive for three laps, on which the Catalyst will gather data and then compare with later laps.

Another feature is live audio coaching, which gives you helpful tips through a Bluetooth headset or a link to the car’s sound system. We will come to this shortly.

The Catalyst’s 7.0in screen shows your lap time on a green background if you’re beating your best time or a red one if you’re lagging behind.

The slight snag is that I’m trying to improve on my own average (from those three laps). What would make more sense is to get Hornsey to drive the three laps and then we swap and I use his times as a target. But there’s quite an element of risk involved in chasing a pro’s lap time, because you have to remember that you’re not playing a computer game: it’s a real car with real things to hit if you go off.

I remember Thruxton’s layout, but not in detail. For the first few laps, I ignore the Catalyst, because it’s more important to get the feel for the car and get back up to speed on which corner follows which. Hornsey chips in occasionally with useful pointers: suggestions to turn in a bit earlier or later where required.

After three laps, the Catalyst has logged my lines and where I’ve been braking and getting back on the throttle. Now that it has this information, it can show me on subsequent laps where I could be turning in earlier or later or going faster. Which it starts doing.

The fastest corner at Thruxton is called Church. It’s probably the most exciting corner of any track in this country, with the possible exception of Fordwater at Goodwood. It’s flat in the Alpine. But, I wondered, what happens if I go through it at, say, 105mph, and the next lap my approach is slower but I’m slightly off line? Will the Catalyst tell me to go a bit quicker, because I’m going slower than the previous lap, or will it know that I am off line and wouldn’t be able to hold 105mph through the corner without running wide at the exit? I asked the boffins later, and apparently the Garmin does work that out.

After about a dozen laps, I’ve remembered the layout properly and have begun to enjoy myself. That’s always a worry. Sure enough, at one point, Hornsey calmly comments: “You’re going to run out of room.” Because he spotted my error early on, because the A110 is so well balanced and because, although I’m rusty, I have done a lot of this, a gentle lift was all that was needed. Miss Catalyst remained completely silent.

Later, back in the pits, we can look at my lines around the circuit and compare them with the ideal one. The Catalyst can also show you ‘opportunities’ for improvement, and that includes segments of video where you were quicker through a corner than before.