This was asked before some time ago, and I can answer similar to how I answered that OOFer...
If you're after them for stylistic reasons alone, then read no further. No idea where you can get them from, but I'm sure someone will be along soon
If it's because of their aerodynamic properties then.... You'll find the design of the Omega (and any car post about mid 80s) is intended to sculpt the air as best it can around the shell, leaving as clean a 'slipstream' as possible. The Omega in particular manages 0.29, which was top of the class back in 1994. Turbulent air is the cause of drag, same as carrying a folded bedsheet vs carrying by dragging it behind you. Little whisp from the door mirrors, some in the engine bay, bits kicking from the wheels, and then a dollop behind the bootlid.
Case 1
Fit deflectors and you're tripping the air from the side of the car, and causing the entire side of the vehicle to become turbulent. OK, so it's causing 'poorer fuel economy' boo hoo, etc, we all run fat old V6/other barges that aren't ever going to be a Prius, but nevertheless, you're actually causing air to jump from the side of the car. Consider a rowing boat with the oars angled a bit to as to generate force - that's what you're doing.
Case 2
there's varying pressure across thr whole bodyshell. That's probbaly unsurprising to most who read this. One are that is common on vehicles is just after the A-pillar. This is where the air pouring off the screen flows round the side. Hold a baking tray under a tap and the water doesn't run down immediately, it flows off in an arc. Same physics. So it's potentially that if you fit deflectors you're inserting this in an area of low pressure, where there's very little airflow, and consequently zero impact on the cars aero, and therefore, no poiint in fitting them, as you're not deflecting any air, as there's no air to deflect
Note: as you drive down the road in the rain. there's a portion of near-static droplets, and above that, a curtain or sheet of free-flowing water, almost like a stream. Guess where the near-stationary air and the fast-flowing air is on that.
That's why, when you lower the window a tad on a fast-moving vehicle, you don't get blasted with 70mph wind - in fact, there's a slight draught which pulls fag smoke/last night's curry out. Yup, area of low pressure doing that. Open the window further and further, and then you get a massive gust blowing your face off - that's the high pressure zone coming into play
And it's the low pressure zone that the deflector is in. So either
a) little real-world benefit - the deflector isn't able to do anything, any more than if it were on the back seat.
b) Worse than no benefit - you're effectively widening the a-pillar, enlarging that low-pressure zone, but at the expense of mucked up aero over the whole bodyside.
As I say, if it's a style thing, worry not, help yourself. But just so long as you know that they're not actually doing anything good, you're not saving 1p every mile or anything. Bit like mudflaps, they cut a bit of grime off the sills, sure, but probably add up to a few quid in fuel every year, too.
EDIT: someone was along soon! hehe
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Topic: Wind deflectors (Read 3730 times)