Airflow your intake.

10th March 2009, 18:13

I've recently been at a windtunnel in the west mids, exploring aerodynamics of certain vehicles. However whilst there I was informed that the upper grille primarily has a vortex/eddies forming behind it and on most older cars lifts the front of the vehicle up via the bonnet (hence the old bonnet flying up and smacking the windscreen on certain sax's) In fact the air drawn in from the lower grille usually escapes via the upper grille and that the primary use of the upper grille is for aesthetic appeal only.

This leads me to think of the tube for the airflow being positioned so high within saxo's behind the upper grille as standard. I mentioned this, and the man then stated that most modern cars nowadays have the intake much lower due to better airflow... I knew this anyway but who exactly has a lower air intake? And where have you positioned it? I very much doubt the airflow will be much greater but it may be food for thought. Many people position it by the fog light but some people worry about water getting into the tube... that said the water still has a long way to travel.

10th March 2009, 18:17

Mine's where the fog used to be (see pic). When I get above a certain speed you can hear the air blowing against the inside of the engine bay.

10th March 2009, 18:19

Ive heard this alot before and to be honest its about right aswel. The fog light is the most normal place as you can get inserts to replace the fog light or some people use morretes and take the middle light out and use that as an air intake. Like you say although you have the risk of water getting in it still has a long way to travel but that is still a risk. Not sure if it could be a risk worth taking though?

10th March 2009, 18:19

water may have a long way to travel but at the speed of gas/water in the inlet system it wouldnt take long to get into the head if you went through some deep water.

10th March 2009, 18:25

Morettes in all honestty are the better way to do it. If you've ever noticed the flow of air (from grime/water marks after a drive) from the headlight you'll see how the air could easily be drawn in there.

I can see why people would be put off by the drawing in of water/muck but water is alot more dense and has more mass per cubic m than most gasses. Alot of water would do damage yes, but would it travel at a speed that was capable to get to the engine. The air filter doesn't act as a vaccuum sucking huge amounts of air in so the water would need some speed?

(generally interested not flagging you down ryan)

10th March 2009, 18:29

Speed going through a stationary puddle will result in the water travelling.

Take a brick for example, hang it on some string, driving at 10mph, how far does that brick travel inside the car from the momentum of the car itself.

Water can be drawn into the engine quite easily as there is some pressure there, (take off the air fiilter and rev the tb and feel the pressure difference. You dont need alot of water to be in the combustion chanber to cause damage, as of course it is more dense than air so wont compress which is why people tend to bend conrods etc...

So its effectively more the speed of the car than the speed of water being thrown into it.

10th March 2009, 18:45

Morrette is definately the best place imo. Higher up the better, and will be pretty much a straight line behind this if you have a relocated battery.

On a summers day when you see the heat rising from the ground? Its called a COLD air feed.

Fog lights are best for brake cooling ducts.

10th March 2009, 18:54

Alex heat rises btw

10th March 2009, 19:02

Quote:

Originally Posted by Ryan

Alex heat rises btw

lol haha

10th March 2009, 19:28

But would it not be hotter at the floor. Thats why its colder at higher alltitude. Obviously were only talking a few inches but.