Probably works as a vortex generator and allows the air coming over the top of the bonnet to break away and go over the roof and off to the sides rather than going full tilt against the windscreen.
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Probably works as a vortex generator and allows the air coming over the top of the bonnet to break away and go over the roof and off to the sides rather than going full tilt against the windscreen.
Does anyone have a pic of the plate that goes on the top of the spare wheel mount? My stage 1 has this same mount but has no top plate. I have the bolts but that's all. Cheers
Attachment 174552
Attachment 174553
is whats on mine
available on ebay etc
Yes, I think you are right.
Without the tyre mounted the wind screen washer water goes up and out to the sides in a smooth pattern and hence in the full sweep of the wiper blades.
With the tyre mounted, the water is pulled towards the centre and slightly downwards with an oscillating/turbulent pattern of movement on the wind screen on both water jets and hence slightly towards the outside sweep area of the wiper blades.
235/85 16 Bridgestone muddies tyre. When I ran the old 7.50/16 Dunlops they were a skinnier tyre and thus slightly flatter on the bonnet, the pattern if I recall was slight taller up the window but still pulled towards the centre.
A study tested it in a wind tunnel, the result was an improved cd with tyre on bonnet.
Study link here:
Wheel on Bonnet = Aerodynamic improvement