Wednesday 4 September 2013

Electronic Throttle Controllers

Drive By Wire
Another example of how the third generation MX-5 became more technologically advanced than the older models is the throttle pedal. The NC Roadster has a modern electronic throttle meaning there is no traditional mechanical cable linkage. Now before you start panicing that your gas pedal isn't connected to anything, relax. Like most modern cars the pedal is connected by wires to the PCM which is connected to an actuator on the throttle body. The voltage signal generated by the pedal is interpreted by the car's brain and translated into opening the throttle a corresponding amount.
This means you can play with that signal generated by the pedal and do some interesting things. If you've ever wanted to be at full throttle without needing to put your foot fully to the floor, read on. Throttle controllers work by changing the throttle sensitivity calibration so that if you move the pedal just a little, the throttle opens wider than normal, this is referred to as "sport mode" and can help reduce perceived lag in the pedal action where the engine doesn't quite respond in the way you think it ought to. The controllers can work the opposite way too, reducing the pedal sensitivity so that for a given pedal movement the throttle opens less than normal. This is normally marketed as "economy mode" and is said to save fuel.
Some will say these gadgets are pointless as they don't add any power, and they don't do anything you can't do yourself by pressing the pedal harder or softer. Others will say they make the car feel more sprightly, are cheaper than a custom re-map, and have a cool display you can mount on the dashboard and have buttons to play with. I suppose there is a certain appeal of having a sort of "Sport" button in your car. There're a range of devices available and they tend to cost around £100-£200. Well known tuning brands such as Apexi, Blitz, and Buddy Club offer them, there's the Taiwanese D1 Spec, and there are also Chinese imports such as the Tros "Potent Booster". They all do pretty much the same thing, with a range of economy, normal, and sport modes. Whether or not there is any real-world benefit to fitting a throttle controller I will leave up to you.

There is one device in particular I want to mention and that is the 3-Drive BLP by Japanese company Pivot. This controller differs from others by offering an adjustable automatic throttle blipping feature on downshifts. This means during spirited driving you no longer have to use the old "heel & toe" technique, you can rely on technology to do this for you and instead focus on braking and hitting the apex. Here's a video showing how it works.