68 replies to this topic

[JimmyJamJerusalem]

Ok so Louvre positioning.....

I'm not sure what the best position for them.

Snoop was about the first car I remember to fit these and they look spot on! I think this seems to be the designed position as they seem to just 'fit' there, but is it the most functional position....?

Here's Snoops position nice and forward




But when I check RCVaughn's lo0uvres they seem further back




Now is this a more practical position (although slightly less pleasing aesthetically)?

I'm not quite sure how the high pressure in the wheel arch will behave and therefore which position would be most effective.

Which of these two scenarios seems the most realistic? Please my understanding of this is not great so please feel free to chip in with suggestions.

Scenario A



Scenario B

[techieboy]

Go for where they fit most naturally. I can't believe it'll make any significant difference to their performance if they're positioned 10-20mm forwards or backwards.

[Winstar]

High pressure in front of the tyre but the bit behind the light will be low pressure, the high pressure bit you will be trying to relive will be at the back of the wheel arch from air scooped up and thrown back by the wheel

[FLD]

The high pressure is at the back of the wheel arch. If you're venting the pressure out of the arch then a vent out the side would be more effective from a performance view. I spoke to my friend at radical about these and there's a multiple function issue. For a simple vent it would make more sense to have the louvre down (less drag) rather than up. The radical with these sort of vents has the louvre up too. The theory is that the upward louvre acts as a turbulator disrupting the airflow over the large flat front area and so reduces front end lift. This was the result of the wind tunnel testing at radical. I have just assumed it works the same on a VX. You should fit louvres and those curved in sills that the badster runs!

[JimmyJamJerusalem]

So as far as relieving the pressure at the back of the arch would it be deisrable to push the louvres further back again to this sort of position?



Or would the standard position AND a vent at the back be more desirbale?

[techieboy]

In which case, wouldn't it be better to do something like Joe did

[Winstar]

The high pressure is at the back of the wheel arch. If you're venting the pressure out of the arch then a vent out the side would be more effective from a performance view. I spoke to my friend at radical about these and there's a multiple function issue. For a simple vent it would make more sense to have the louvre down (less drag) rather than up. The radical with these sort of vents has the louvre up too. The theory is that the upward louvre acts as a turbulator disrupting the airflow over the large flat front area and so reduces front end lift. This was the result of the wind tunnel testing at radical. I have just assumed it works the same on a VX.

You should fit louvres and those curved in sills that the badster runs!

not sure that's so applicable to the VX as to airflow is pretty turbulant due to the blunt nose, however louvers shoild also create a bit of a venturi effect to suck air out.

[FLD]

what techie said! Also true about the venturi effect. Its all rather complicated. Either way you would need to cut the arch liner and duct it to the top louvres.

Edited by FLD, 09 February 2012 - 11:47 AM.

[Winstar]

actually if you look at the pressure contours on the VX then the wheel arches are not really where you need to improve, it's the 2 flat areas either side of the rad inlet acting as air dams. You need to move the air round or over the car more smoothy.

Edited by Winstar, 09 February 2012 - 11:51 AM.

[Mike (Cliffie)]

So the lower Joe type cuts without the top louvres but with the arch liner vented is OK?

[FLD]

actually if you look at the pressure contours on the VX then the wheel arches are not really where you need to improve, it's the 2 flat areas either side of the rad inlet acting as air dams. You need to move the air round or over the car more smoothy.

If you remove this pressure area then a front splitter would become less effective. Not a bad thing on a standard car but not so good for anyone with a big wing?? Although they have a small effect would canards be good here? Lifts the air up on the side of the flat front area??

[coople]

Would canards not dissrupt the flow to the radiator intakes at the back?

[FLD]

Would canards not dissrupt the flow to the radiator intakes at the back?

possibly. Side skirts might then help that by stopping air dissapearing round the sills to underneath the car.

[Mike (Cliffie)]

The vents on the bonnet are to let hot air out are they not?

[chris_uk]

Just put them where they look best, it will be better with the lourve than without but i cant see it making too much difference in position. What we taliking 100mm between forward and back?

Edited by chris_uk, 09 February 2012 - 02:23 PM.

[FLD]

The vents on the bonnet are to let hot air out are they not?

i thiink it was the side vents.

[coople]

The vents on the bonnet are to let hot air out are they not?

i thiink it was the side vents.

Yeah I did mean the oil cooler and intercooler vents. Not the water rad.

[mbes2]

SteveA also has these fitted, they do look very smart and would work at high speed on track. Jimmy, found this link, might be worth a read http://auto-racing.s...-on-prototypes/

[chris]

[The Batman]

i have no idea what im looking at but i sort of want to print it onto canvas and hang it on my wall