What is intermediate throttle?
01/26/2011
Our online platform is called Zwischengas, a term that will certainly mean something to classic car enthusiasts. In modern times, the "ability" to drive with intermediate throttle has been somewhat lost, or is even (artificially) taken over by the engine electronics in modern vehicles.
In the early days of the automobile and in racing, however, intermediate throttle was essential for a long time. A reader's question and the corresponding answer from November 15, 1929 are therefore quoted here:
"Question. Shifting gears with intermediate throttle. As the son of a subscriber, I would like to ask you the following question, which I would like to thank you in advance for answering in the "A.-R.". Is there an advantage to double clutching when changing gear and what is it ? I drive a large German touring car model 1920.
Answer. Shifting gears with a double clutch, or rather shifting gears with an intermediate throttle, is a very good method, although it is not taught by all driving instructors. For example, if you want to go down from third gear to second gear, you do not have to wait until the car is running slowly enough when shifting with a double clutch, nor do you have to brake the car; instead, when the car has reached the approximate maximum speed of the lower gear, you can disengage the clutch, move the gearshift to neutral, engage the clutch and apply intermediate throttle, disengage the clutch again and select the lower gear, whereby the same gear engages without any noise. But double clutching (here without intermediate throttle) also offers advantages when shifting up, especially when moving from the second-highest to the highest or direct gear. Shifting gears with a double clutch is not exactly easy for beginners.
It is particularly important to let the engine drop down from maximum revs to a speed that is necessary for quiet shifting when you have applied the intermediate throttle. Hearing and driving feel are the deciding factors here."
There is little to add to this. Except that, in addition to protecting the gearbox and synchronizer rings, it can of course be important, especially in racing, to reduce the drag torque of the engine (after engaging the clutch without throttle, the engine brakes the drive axle, so to speak), which becomes a danger in curves, with intermediate throttle. And of course, downshifting with intermediate throttle is even more complicated in racing, as the brakes still have to be applied at the same time as the throttle when slowing down before corners. Many racing drivers have therefore had their pedals adjusted accordingly to make this easier.
And another note: The term "intermediate throttle" does not exist as a single word in other languages, the English, for example, speak of "double clutch", but that's really only half the story, a complete translation would probably be something like "double clutching with throttle response". Sometimes the German language is shorter and more concise.
