MX-5 NC1 1.8 gear ratios

[klheavytools]

Hello Everybody!

I saw the gear ratios in the tune for the 6-speed NC, but i have a 5 speed one.
Does this affect anything or should I just ignore it?
Btw, the tune works well!

[Ugnius @ VersaTune]

When a VersaTuner tune is flashed, a proper base tune for your ECU will be loaded, only the necessary tables will be changed and it will be flashed back. The tune does not change the gear ratios, so they will not be modified.

[klheavytools]

Thanks Ugnius, i know it doesn't change the hardware. But does it change maybe the displayed speed, based on the RPM and the stored gear ratios? Why is this data in the tune?

[mituc]

It will not affect the speed displayed on the dash (or OBD, which is also the source input for the dash speedo which applies some multiplication factor for it) because that's read either from the gearbox final gear or from the ABS sensors. However, that data is in the tune because it is needed to calculate the shift points, and also correlate the calculated speed with the actual speed, this data being fed to the stability control module.

[klheavytools]

Thanks Mituc!
Do you recommend to change it for the 5 speed ratios, or it doesn't give extra to it?

[Ugnius @ VersaTune]

Gear ratios are not changed in the prebuilt NC1 1.8l tune. When you load it in your copy of VersaTuner, you will see 5 speed ratios. When someone with the 6 speed transmission loads the same tune, they will see 6 speed ratios. There's no need for you to change anything, just flash it to your car and the correct gear ratios will be applied. You would only need to change the gear ratios if you replaced or modified the transmission.

[klheavytools]

Well ok, thanks. I checked it again. The 6th speed ratio is just the duplicated 5th, that misled me.