Gearbox question 3

[toyroom]

You know how boost is limited in first and second? Well, as there are no gearbox sensors, how does it know what gear you are in ? We thought that the ratio of wheel speed and flywheel speed would answer this, BUT....What if the wheels are spinning?.....80mph wheels and 'box at 3,000 revs is fourth or fifth (third in mine) and there is quite a bit of overlap between 2nd and 3rd as well....How does it know...Does it calculate the time taken to get to the wheel speed (to eliminate wheelspin data error) or what ????!! Thanks !!

[Esprit2]

Even if the wheel is spinning, there's a fixed gear ratio relationship between engine speed and wheel speed. The ECU knows the engine speed, and there are wheel speed sensors for the ABS. The current gear ratio is simple math.

There would have to be wicked clutch slippage to throw it off.

Regards,
Tim Engel

[toyroom]

Clutch slippage would mean fast engine slow wheels anyway so it would calculate first or second gear. Yes, never thought this through properly. sorry!

[toyroom]

Clutch slippage would mean fast engine slow wheels anyway so it would calculate first or second gear. Yes, never thought this through properly. sorry!