More holes

[RobGTO3]

Thought some of you might be interested to see the extra air intakes put under my car by Skip at Bespoke. I already had the tunnel cooling mod, but the added cooling is dramatic, running at about 10 degrees cooler sitting on the motorway and a much more effective 'cool down' lap after hot laps. I'm interested to hear if anyone thinks this will have had much of an effect on aerodynamics. Rob

[RobGTO3]

[andygtt]

looks very effective

[951]

RobGTO3 said:

I'm interested to hear if anyone thinks this will have had much of an effect on aerodynamics. Rob

If air does actually go into the ducts it will obviously increase pressure (reduce the low pressure) under the car and so can only adversely affect rear end downforce?

Where does the air go to, and more to the point how does it get out?

[Adrian W]

I looked at putting Naca ducts in the side pieces and the tunnel, I was told it's a no no

[Hollowpockets]

I would have thought it goes against the principles of aero stuff, probably does cool it well though. Depends what you want from the car.

I thought about a couple of naca ducts in the top of the arches to feed cold air to the rear brakes.

After the races (they had been cooling for a few minutes and cool down laps) but my front brakes were 100 degrees, rears were 120! Rears need cooled!

Graham

[Adrian W]

Graham, what about a duct in the sill, then a bit of flat ducting, then a bit of flexi into the middle of the disc.

[RobGTO3]

Adrian W said:

I looked at putting Naca ducts in the side pieces and the tunnel, I was told it's a no no

Was that from an aero or from a cooling point of view Adrian? Theres no doubt that I could do with some more grip, so I'm hoping I've not sacrificed too much downforce in the endeavor of not cooking the old girl.

[andygtt]

IMO the effect on downforce will be minimal, especially as there are already quite a few holes in the underfloor disrupting an effective under tray effect.

In truth the main trick is getting the air out of the engine bay rather than in.

[StreetDragster]

Are there any well known improvements to be made to the rear clam for getting air out? For cooling rather than aerodynamics.

Thanks

Matt

[Adrian W]

RobGTO3 said:

Adrian W said:

I looked at putting Naca ducts in the side pieces and the tunnel, I was told it's a no no

Was that from an aero or from a cooling point of view Adrian? Theres no doubt that I could do with some more grip, so I'm hoping I've not sacrificed too much downforce in the endeavor of not cooking the old girl.

I was advised from an aero/lift point of view.

The most effective way to improve cooling airflow is to remove the rear grills.

[RobGTO3]

The trouble with having all of these individual mods is not having millions to spend on r&d but I'd be astonished if the extra cooling from removing the mesh was as effective. I might do that next and see if the temps drop even further.

[Adrian W]

RobGTO3 said:

The trouble with having all of these individual mods is not having millions to spend on r&d but I'd be astonished if the extra cooling from removing the mesh was as effective. I might do that next and see if the temps drop even further.

Prepare to be astonished

Edited by Adrian W on Thursday 18th July 07:59

[GTO600]

Rob, where are you measuring the temperature that is showing 10 deg lower ?

[chuntington101]

Didn't paul do a similar thing in his race car?

Why would NACA ducts in the underfloor effect the downforce? Surely they would be taking air from under the car, thuis reducing presure under the car? or have i got this totally mixed up? lol

[andygtt]

The floor under the car gets higher towards the rear of the car, this means the air going under the creates a vacume at the rear of the car and effectively sucks the car to the ground at the rear.

Holes in the underside to allow the air to escape (into the engine bay etc) destroy this vacume and thus you would loose the downforce... although to be an effective underfloor vacume you need barriers to stop air being sucked under the car from the sides or from the wheel arches etc etc... which the noble doesnt have at all!

its arguable if the noble underside gives any measurable downforce at all... my view is it just stops drag and tidies the air up ready for it to go into the diffuser, (which is also a very important role).

[key750]

this is my improvement to combat the high temperatures of the Mediterranean climate:





at high speed the flow is not disturbed under the car... while the slow and stop the bottom is much more permeable

[Adrian W]

very nice, I take it you don't have a track day sump

[RobGTO3]

Adrian W said:

Prepare to be astonished

Edited by Adrian W on Thursday 18th July 07:59

Ok..

[RobGTO3]

GTO600 said:

Rob, where are you measuring the temperature that is showing 10 deg lower ?

There is an extra oil temp gauge that shows engine and gearbox temperature. Both are show significantly lower, especially the gearbox when sitting at highish speed. Rob