A short look at FIA regulations for Super Touring gearboxes (for the upcoming content).

I am a massive fan of Super Touring cars, and I am glad to see that they're beginning to show up in simracing games. That being said these cars in their portrayals (often unofficial mods) usually do not get the gearboxes working as they should and take away from the experience of how it'd be to actually drive some of these cars, so in this post I figured I'd share the technical regulations. To provide a more comprehensive understanding of what the super touring cars were (and were not) allowed I looked through some of the Appendix J documents from the year 1995 to the year 2000.

The regulation on Super Touring gearboxes specifically says:

"The clutch and its control are free but automatic operation of the clutch is not allowed and. in the case of a hydraulic dutch, the liquid tank must not be situated in the cockpit. The clutch must be activated by the driver's feet. Automatic dedutching devices in the event of over-reving are permitted, if these devices have no other functions, if the declutching occurs at an engine speed higher than that foreseen by the limiter and if it is homologated (2 500 units)... ...Semi-automatic and automatic gearboxes are forbidden"

Basically they did have over-rev protection on downshifts by allowing a device to de-clutch the car if the rev limiter (7200rpm) was exceeded but indeed no form of downshift protection was otherwise allowed.In 1998 they added this stipulation. As we also see they were expressly prohibited semi-automatic and automatic gearboxes. The FIA defined a semi-automatic gearbox (in 1996, the 1995 appendix had no listed definition) as:

"One which, when the driver calls for a gear change, takes over the control of one or more of the engine, clutch and gear selectors momentarily to enable the gear to be engaged."

What this means is these cars, unlike the Class A cars (DTM) were not allowed to have gearboxes which electrically assist with the clutch or throttle. In the year 1998 however this stipulation was further added:

"It is permitted to have a sensor on the gear lever to initiate a power cut, to have a single, unique timed cut to rail the gears in the ECU and to have a sensor in the gear box to indicate the successful selection of the gear."

So from 1998 onwards the cars did cut the throttle on upshifts on their own, but this was the maximum amount of electronic assist that these cars were ever allowed in their working life. It is unclear if this throttle cut was expressly forbidden prior to 1998, but footage of BTCC and STCC from those periods show drivers manually releasing throttle on some cars. Possible it varied from car-to-car.

Automobilista 2 has definitely shown its capacity for complex gearbox modeling. So the proper representation of gearboxes for these cars would be sequential gearboxes in a model in which clutchless shifts are primarily viable on the proper rev range, and which the driver manually has to blip the throttle on downshift (and until 1998, manually release the throttle on upshift too to avoid rising the revs). If possible, clutchless shifts on incorrect rev ranges should run the risk of mis-shifting.

I hope that this implementation is paid heed to in the upcoming content.