tbh i don’t really see the point of fitting a spoiler in an MX5. maybe its my taste in things etc etc.
If however you want to use a functional spoiler it has to be a rather large motorsport type spoiler. And you would have to drive the car with the roof up - otherwise it will be pointless.
I have actually come across a video that they analysed the effect of a spoiler in an MX5. In summary you need a large and wide rear spoiler to get the most downforce. A small spoiler is in the wake of the car so even with the roof up and it wont have any effect.
Here is the video.
