Thread: Bonnet scoop on RRC

Hi All,

Blackrangie - Appreciate the extra information you supplied on positions of holes in bonnet to direct air down the sides
and rear of engine bay and removal of rear wheel arches as a means of evacuating air out of engine bay.

Look forward to any results you can give in the future.

I also can see Davo's point of view in that in the Disco 1 post many have mentioned that improved (directed) airflow
through the radiator is the only way to cool an engine and where's he's from where 40 degree is a pleasant day and
alterations like mine could for example come back and bite you badly in the middle of nowhere.

As Gavin has said both you have a shared interest at heart ....

On further driving of my Rangie yesterday the only scientific evidence I can give is the same as Tombie .... My radio used to get
extremely hot to touch ...in fact I'd shy away from putting CD's on a long drive ...... afraid they would get stuck in the unit.

Shane - Double Chevron could probably throw light on the heat required to warp a CD ... he's pretty good on obscure facts

Now my radio is warm to touch ..... but nothing Id concern myself with.

Also .... put it down to dumb luck the positioning of my scoop the front airflow is over the plentinum chamber and the rear slot towards the back
of the firewall ..... no smoke test done (I was actually joking in an earlier post) ... However she seems far more responsive in acceleration.

I might just use Davo's method to produce smoke as a test ..... better still ... I'll wait till he builds a wind tunnel ... drive up (hopefully Rangie doesn't overheat) and use it.

Finally ...... I could have "Go Fast Bonnet Scoop" syndrome which I hear is very contagious .... or my other thought is that cooling the plentinum chamber
the air into the cylinder is now cooler and has improved fuel burning ...... HOW'S THAT'S FOR OPENING A NEW CAN OF WORMS"

This is where I insert "the disclaimer" I'm an untrained professional please do not try this at home yourself


Cheers

Baggy

Originally Posted by blackrangie

Again on the attack

I see you can't differentiate between an actual personal attack, (name-calling, questioning parental genetics, etc.) and a sarcastic request for evidence which you keep managing to avoid presenting, so I'll make it simple.

You say your scoop will work. Then show us how. As simple as that.

I say it won't, because I've done a lot of research and I've managed to learn one or two things along the way. One of those things was that you can't just shove air into a radiator or an engine bay. I know because I tried it. Like most of the things I tried! So, considering you've put more effort into responding to me than researching what I've bothered to try and explain to you, go on and do that research. Prove me wrong - and I'll put a big scoop on too!

Now the onus is on you to provide that proof - anything else is just squeaking on the internet.

Originally Posted by Baggy

Hi All,

Blackrangie - Appreciate the extra information you supplied on positions of holes in bonnet to direct air down the sides
and rear of engine bay and removal of rear wheel arches as a means of evacuating air out of engine bay.

Look forward to any results you can give in the future.

I also can see Davo's point of view in that in the Disco 1 post many have mentioned that improved (directed) airflow
through the radiator is the only way to cool an engine and where's he's from where 40 degree is a pleasant day and
alterations like mine could for example come back and bite you badly in the middle of nowhere.

As Gavin has said both you have a shared interest at heart ....

On further driving of my Rangie yesterday the only scientific evidence I can give is the same as Tombie .... My radio used to get
extremely hot to touch ...in fact I'd shy away from putting CD's on a long drive ...... afraid they would get stuck in the unit.

Shane - Double Chevron could probably throw light on the heat required to warp a CD ... he's pretty good on obscure facts

Now my radio is warm to touch ..... but nothing Id concern myself with.

Also .... put it down to dumb luck the positioning of my scoop the front airflow is over the plentinum chamber and the rear slot towards the back
of the firewall ..... no smoke test done (I was actually joking in an earlier post) ... However she seems far more responsive in acceleration.

I might just use Davo's method to produce smoke as a test ..... better still ... I'll wait till he builds a wind tunnel ... drive up (hopefully Rangie doesn't overheat) and use it.

Finally ...... I could have "Go Fast Bonnet Scoop" syndrome which I hear is very contagious .... or my other thought is that cooling the plentinum chamber
the air into the cylinder is now cooler and has improved fuel burning ...... HOW'S THAT'S FOR OPENING A NEW CAN OF WORMS"

This is where I insert "the disclaimer" I'm an untrained professional please do not try this at home yourself


Cheers

Baggy

Does your Rangie have the CD player down in front of the gear shifter? If that's the case, then you may well have managed to get the air down along the back of the engine and along the bulkhead, which wouldn't be a bad thing. But as you say so correctly, it's all guesswork, which is the crux of the problem. (I should know - I've made a lot of bad guesses on this subject!)

Now if you really want to cool that plenum, you'll need an intercooler . . . oh no, I've gone cross-eyed . . .

But seriously, I'd recommend some sort of fan and an incense stick, just to see. It's amazing what odd things air will do that you couldn't imagine.

wow ...

if you take a step back for a minute - and really look at it and think about it...

Who seriously gives a flying frack if it works or not? Does it look cool? Yes! Can it be functional? Yes!

Altho it does make one wonder what would happen with water coming over the bonnet?
But I like the look of the scoop that Blackrangie has put on his. I am thinking Bitsy might look good with it on as well.
Functional or not

Originally Posted by Davo

I see you can't differentiate between an actual personal attack, (name-calling, questioning parental genetics, etc.) and a sarcastic request for evidence which you keep managing to avoid presenting, so I'll make it simple.

You say your scoop will work. Then show us how. As simple as that.

I say it won't, because I've done a lot of research and I've managed to learn one or two things along the way. One of those things was that you can't just shove air into a radiator or an engine bay. I know because I tried it. Like most of the things I tried! So, considering you've put more effort into responding to me than researching what I've bothered to try and explain to you, go on and do that research. Prove me wrong - and I'll put a big scoop on too!

Now the onus is on you to provide that proof - anything else is just squeaking on the internet.

Again on the attack

Ok, enough is enough with the back and forth here please - we get that there's differing views here, please keep it civil guys.

Personally I think a forward facing vent at speed would help push the hot air out from under the bonnet down below the engine. Yes, testing would be good, but I think anything would help to be honest.

Originally Posted by Homestar

Ok, enough is enough with the back and forth here please - we get that there's differing views here, please keep it civil guys.

Personally I think a forward facing vent at speed would help push the hot air out from under the bonnet down below the engine. Yes, testing would be good, but I think anything would help to be honest.

Agreed

Originally Posted by DiscoMick

I don't understand aerodynamics, but I was thinking that aircraft wings are shaped to cause air to flow over the top, so that causes the air under the wing to lift up, causing the wing to lift.
So if the aim is to get hot air out of the engine bay, then a bonnet should be shaped like a wing so the outside air flows over the top, while the hot air underneath is drawn up and out the rear of the scoop.
That would also cause air to be drawn thru the radiator and then up and out the rear.
Does that sound right?

No.

Think more like a venturi. he faster the air is flowing, the less pressure. So, if you have air flowing over a bonnet, it is at a lower pressure than the air under the bonnet that isn't moving. If you drill a hole in the bonnet, the air under the bonnet will move through that hole to the lower pressure area above the bonnet where the air is moving.
But, for a car, you need to take into account the high pressure area caused by the windscreen.
Lots of fluid modelling involved.