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MG Midget and Sprite Technical - Wing Vents

I know that wing vents get discussed fairly often, but I don't know anyone who has actually bothered fitting any.

So... before I finish painting my wings (sometime this summer maybe) I am really tempted to put in some louvers. Partly for reducing the heat and high pressure under the bonnet area, but mostly because I am a bit childish and louvers = racing car = cool!

I think from a functional persepective they would work best orientated vertical (left pic). But then I would have to mount them quite low down due to the curve of the wing, so maybe not that good after all?

Aesthetically I think they work best horizontally orientated near the top of the wing (right pic). I think they would still work well up here too.

I discounted putting them on the bonnet as I couldn't think of a practical way of stopping rain getting in and soaking the electrics/carb/whatever.

What do you think?

Cheers,
Malcolm


Malcolm Le Chevalier

Have a look at Range Rover or something along the lines of Ford XR turbo bonnet louvre.
Did metros have a vent?
The central heating louvres don't exactly look great.IMO.
Alan
Alan Anstead

Well, they will be welded in and painted up with the wing if that makes a difference? Something like the attached.

Malcolm Le Chevalier

Er, that's red insulation tape not welding!

Less is more in my book, I'd keep the classic clean lines of the original car.

I've considered them myself in the past but glad I didn't now. I thought they would be a good way of keeping temps down but it's turned that my car runs quite cold as it is.

As you point out some form of ventilation could reduce the internal drag of the car but I think they would need to be bigger to let out the masses of air coming in through the grille. My car seems to hit its top speed fairly quickly but then hits the proverbial brick wall. I wonder if opening up the grille as I have (either side of the rad) is creating loads of drag so I've considered blanking the sides off to see if it helps. I think Daniel Stapelton has discussed this before. I'm not expecting it to suddenly add loads of top speed so probably why I've not bothered yet!!

A lot of the race Midgets have the lower rear of the wings cut away to aid ventilation and drag and it looks ok - on a race car anyway.

The Metro Turbo had extra vents in the bonnet which had a plastic tray incorporated into them and a pipe running to the front to drain water away.
john payne

Here's the very successful David Morrison's car showing off its cut away wings at Loton Park:

john payne

Here's the Metro Turbo with extra vents, the standard Metro had the two outer ones (left is heater inlet, right is a dummy). This photo makes me want one again!

john payne

And if you want the ultimate Metro bonnet vent:

john payne

Malclom,

if it's purely aesthetic then vertically at the bottom of the wing is my choice.
If it's functional then what about a flap (operated thermostatically!) such as the heating flaps either side of the transmission tunnel.
Jeremy Tickle

spot of bonnet venting on mine. Left hand one lets LOADS of heat out. was trying to take a picture of the heat haze from it after 25 mins of driving. It sits above the exhaust manifold.

I could fit something underneath it but seems to be fine. Light rain results in the passenger windscreen being dry from the heat coming out. And the front end lift at 90+ mph has been eliminated...

The other one is an inlet which also serves to cover up the MAP sensor which is a little bit proud.

Have also thought about wing vents but no need now there's a bonnet hole.

Rob Armstrong

Recently I read in an old (1955) copy of Motor Sport a description of someone using a feather duster to test the airflow over their car to determine the best place to locate louvres to reduce under-bonnet temperature.

This, highly scientific, test showed relatively dead air (i.e. high pressure) over the bonnet but good flow alongside the wings, where the low pressure would help to draw air out of the engine bay.

Just a thought - when does the heat cause a problem? Is it when the car is moving or when it's crawling in traffic? High temperatures on the move would steer me towards wing vents. I suspect that bonnet louvres would help if it's overheating or fuel vaporisation when stationery or crawling.


Has anyone found any ways of reducing under-bonnet temperatures without cutting holes? My fuel lines and float chambers are currently wrapped in rather ugly foil to eliminate a slight fuel vaporisation problem.
Colin Mee

Malc

For temp the left photo is the most funtional the right side photo the air is not as effective... but for high air oressure relief you will need more venting


thoose louvers will look great once there formed in and i think installed in the left photo will work very well ... id add a couple studs on the back side and make an ally plate that can be placed on the back side of the wing and secured with a couple of wing nuts for winter time and wet season driving

ive heard of using cigerettes and smokey wood and strands of yarn to see the air flow... never tried it though

for me... i want them for temp because in missouri its real hell in summer ... even the dead sweat as they rise

one area thats always looked interesting with out wing vents is the back side of the wheel arch with a small electric fan to help suck the air out and around the wheel... its been twlked about briefly here and there but i dont know of anyone going all the way with that idea

prop
prop

Malcolm
My engine bay was getting fairly hot so I cut these in.
Driving along you can feel the heat being pushed out
My front end is fibreglass but should be no different for yours


Dave Pratt

Dave

that looks really nice i like that... if you added a 1/2 inch spacer between the sheet metal and the mesh i have to belive you would get some serious sucking action out of the engine bay and / or adding a small louvered lid to the leading edge of the sheet metal slot would also create a nice low pressure area over the mesh

i never realized how thick the sheet metal is but clearly enough id think to creat a depression

its all about the airplane wing effect

prop
prop

Dave ...

did you roll the cut out or is it just cut and fed smooth
prop

I went for the bonnet venting.
Like Collin says when does the heat becomes a problem: driving or in trafficjam?
Mine has a K series in and gets hot while in very slow traffic in combination with hot weather.
So I placed the louvres above the exhaustmanifold where most heat comes from (like Rob's).
To make things symmetric I also had them on the otherside of the bonnet.
Like Rob says its amazing to see the heat that comes out!

Beside function I also like the period looks of louvres.



Arie

Here you can see true the louvres from the inside.

To prevent rain coming in when the car is outside I simply put on flexible magnetic plates cut to size on the inside, cheap and very effective.

Arie

Here you see one of the magnetic louvres cover, lets no water thrue at all.


Arie

But the master of wingvents is ofcourse Carl Bintclif.


Malcom, if you go for wingvents I would personaly go for the vertical option(looks wise).



Arie

I mean vertical like your first photo.
Maybe its not completely needed on your midget but its also fun to personalize your midget.
Just give it some time to think over all these options others have done.


Here is Eddie Browns supercharged Kseries midget who has both bonnetvents and wing vents.
There is deffenitly a functional need for vents in his car. ;)

Arie

i used these
http://www.carbuildersolutions.com/uk/self-adhesive-moulded-abs-bonnet-vents-gloss-black

just cut a hole and stick them on.



Andy Phillips (frankenfrog)

and on the top i have this, from a toyota pickup intercooler intake.


Andy Phillips (frankenfrog)

Arie

Carl promised us wing vents... im still holding him to it... granted that was 5 years ago

but still

prop
prop

Thanks for all the ideas everyone.

Heat under the bonnet has notbeen a problem, it's just that less heat is better!

Still mulling over what I want to do. The fact I don't have any grinder cutting discs at the moment is stopping me going ahead and chopping big holes in my wings. Probably for the best! :-)

Malcolm
Malcolm Le Chevalier

especially if you have a look at the price of new ones!
Rob Armstrong

I don't seem to be able to add my picture, still it's one found in a book...

Offset louvres in the bonnet, over the exhaust manifold area will allow lots of under bonnet heat to escape when the car is stationery or in slow moving traffic. Also, as someone else stated - you can see a heat haze above the louvres.

Wing vents - like the ones Carl made, and everyone wants probably achieve less under bonnet heat reduction in traffic but equally so achieve much more at highway speeds in that they contribute to a reduction in 'lift' and reduce 'service drag'. Put another way they may reduce the CDa of the car and increase top speed/improve mpg.

Cut away rear sections of wings are more difficult to achieve than might be supposed because you are cutting away the section of the wing where it bolts to the car so unless you have a fibreglass wing it's not easily achieved.
Daniel Stapleton

I once read this book (pictured), but it didn't help...

But thinking more... the most practical application of louvring is to concentrate them towards the rear of the bonnet on the exhaust side of the car, however the heat haze (as it is a 1500) that will emanate from them on a hot day in traffic may be distracting.

:-D

Malcolm Le Chevalier

Malc

i think if your going to place them on the bonnet id copy arie... id think the distraction will be mostly sitting in traffic

im alsonguessinf its only stifling hot for a few weeks out of the summer...here its mkst unbearable between mid july to mid aug.

Plus you have to remember arie has a duel exhaust K series approching 2000 cc so he is pumping out alot more puppy raping, planet killing heat and toxins then the rest of us... so his vents will be working over time compared to our bunny friendly flower powered efficiant engines

Prop
prop

The heat haze can only be seen when standing still in traffic, as soon as your in motion its gone.
I placed my louvres as much to the rear as possible, couldn't go further to the back because of the bonnetsidewarts "beam".

Only had heat troubles when in trafficjam in hot weather, never when the car was on normal or extreme speed.
So bonnet louvres was the way to go for me.
But to be honest the heat issue was caused by something else which I fixed before putting in the louvres.
But by that time I so liked the image in my head of having these louvres I went on with having them anyway. ;)

Malcom, take your time before getting the grinder out, it took me atleast 3 to 4 years of planning/drawing/calculating before actualy taking the irreversible step.


Oh, its not in the original bonnet, still have that on just in case... ;)



Arie

I like the ones in Andy's link. They look really nice. I presume that you fit them with the "bump" at the front to create suction. They would probably make people think I have something more than a 1098 under the bonnet. LOL.
Bernie Higginson

Hi Bernie,
Yes I fitted them with the bump at the front.

However after recommending them I have decided to design and make some new ones based on a combination of a lot of examples on this thread and others and a beautiful picture of an AH 3000 I saw.

Also it's been 42 degrees here for the past two weeks and my electric fans are going into melt down !
Andy Phillips (frankenfrog)

Image shamelessly swiped from Prop's thread on the General board.

How 'bout those wing vents Malcolm? I checked the 'net and they're still available as repro parts. Lovely but pricey.

Greybeard

Greybeard,
I think he's overdone it - surely the big louvre in the bonnet should be enough? LOL.
Jeremy Tickle

Back in the 70s here in Aust. there was a car called an XU1 Torana which had a set of tripple vents in the guard
They now reproduce the vents and they come with a stepped edge for fitting up to you guards (wings)
Here you go

http://www.ebay.com.au/itm/HOLDEN-LC-LJ-GTR-XU1-WELD-IN-GUARD-FLUTES-1-PAIR-BOTH-SIDES-RARE-SPARES-/262272143120?hash=item3d10a34f10:g:Q60AAOSw0QFXBd9P

The slots would be probably about 180mm ish high

willy
William Revit

The last of the 2nd generation camero z28 had some nice wing louver funtioning vents...

i want to say 1978 thur 1980

i wish i had paid attention to that corvette id snapped a few photos of the wing vents
prop

After a run down the motorway on Friday in 20-ish degrees everything was pretty hot. Most importantly I need a bigger oil cooler, but in the meantime (and because wifey is away and I was bored) I thought I would progress this idea.

My passenger wing had a shonkily cut aerial hole in it, so set to work "tidying" that up.

Now I am done, I don't think like it! I thought just some small vents would be nice and discreet, but it's almost just looks a bit half-arsed with only three vents and making more of a feature of it would look better also, whilst they are lined up against the back of the wing, but they don't line up with the "flow/curve/lines" of the wing.

Basically, I need to stop messing!

Oh well, nothing ventured nothing gained. This wing still needs work before paint, so could have another go at this.

Malc.


Malcolm Le Chevalier

Hey malc

I dont think yours are in a good spot to flow much hot air ... its way to far back and high


check out my movie i made several years back at 1:18 the photo is only about 2 sec long

The vents are in the place it really needs to be in order to suck out must of the hot air effeiantly... sadly these are not funtional just the plasitic stick ons for looks but i always thougbt if you can find them it wouldnt be hard to modify them to be funtional... will they flow much hot air ... goid question ... they are as you mentioned small and discrete

i do like them... i think these were simple oval ... not round or rounded rectangle shaped

http://youtu.be/QT_NgmMR30M
prop

There was warm air coming out when sat idling after a drive, my arm isn't long enough to feel for warm air coming out whilst moving! :-D It should flow as under the bonnet should be fairly high pressure.

Anyway, the main aim was to do something about this aerial hole that someone drilled into the wing at some point.

Malc

Malcolm Le Chevalier

Generally l don't think overheating is a problem when travelling at speed, which is when having vents in a low pressure area would be beneficial. If overheating does occur, it's going to be when at low speeds such as when in heavy traffic. In this situation its probably a good idea to have them on the top of the wings, or in the bonnet. Hot air rises doesn't it?
GuyW

Normally id agree with you guy

I think the heat is worse with higher speed driving esp in the area malc is talking because the engine bay can easily recieve air... it ust cant get rid of it very effeciantly and that exhaust manifold puts out alot of heat that is trapped... the more rpms the more heat is generwted and the more it gets trapped


Malc... yes the placment is fine it will vent heat ... its just not as efficiant as just behind the wheel and up just before the curve... thwts the sweet spot for max heat exchange... not my work but of many that have come before us and there names are written on the arcive walls.... as in Formula 1 race car wind tunnel expert for renualt racing carl (bennington ??)

But if your just covering a hole... yeah your good once you retire out of retirement and back into a proper tax payer you can go back and fix it correctly ... but i dont see any problem with what your goal is...id do the same

prop
prop

My new ones... cardboard version at the moment.
Soon to be drawn up in CAD and laser cut.

42 degrees here, need to do all i can......



Andy Phillips (frankenfrog)

2nd pic

Andy Phillips (frankenfrog)

Andy, can't you make a batch of 100% copies of Carl's and sell us a pair?
Daniel Stapleton

Ive extended them a little since the pictures.

They are at the fab shop at the moment, lets see how they look and perform once finished.
If people like them then i can get a batch made no problem.


Andy Phillips (frankenfrog)

Andy

there " interesting " ... but im with danial X2 can you copy carls ? NOW that would be radical

dont tell Arie ... the poor guy has been waiting for so long for carls wing vents he went out and accidentally got himself married ... just sad what time and pressure will do to a man.

prop
prop

I must say that I rather like Peter Neachell's Z3 vents as illustrated in this months Mascot.
Geoff Mears

My new vents, laser cut from stainles, as yet unpolished.
with some black paper behind for contrast...

Honest opinions please...

Andy Phillips (frankenfrog)

Two vents on top of frogeye grilll, to show the comparative flow area.

Andy Phillips (frankenfrog)

pic 3

Andy Phillips (frankenfrog)

visual effect is v good - but I thought the slats had to be angled (not flat) so as to induce airflow out from the engine bay. Otherwise it may not produce the effect you're looking for.
David Smith

My theory is that when the car is moving the air pressure in the engine bay will be greater than at the sides of the car so that will push the hot air out.

And when stationary the air velocity is not so much anyway so so the main thing is to have enough area to allow an easy flow.



Andy Phillips (frankenfrog)

Leading lower edge curved to follow the arch line would be visually nicer IMO.
G Hawkins

I like them. I would have fitted them very slightly further back. They're bigger than I would have liked BUT as you live in a very hot country it's quite understandable you need them that size. As I always say, its your car, and as long as you are happy, who cares what others think. :)
J White

Well they ate not fitted yet just held on with double sided tape . so I can experiment with the position, the reason they are the shape they are and in that position is to match the position of the 'vee' made by the foot well and the whhel arch.
I think having a radius to match the wheel arch is a nice idea and as I had a spare set made might experiment with twisting the slats
Andy Phillips (frankenfrog)

I'm thing of fitting the ABS moulded vents that Andy mentioned but am not sure of the best way to cut the holes in the side of the wings without distorting them.
Has anyone had experience of actually doing this? Any advice gratefully received.

Tony
Tony Wood

I've not actually cut vents but windows in vans etc - tool called from memory a 'Monodex' sheet metal cutter - hand operated - need to drill a hole to start and at any tight corners - (similar procedure to using a jig saw. It actually shears out a small strip of metal between the side anvils as it cuts.

Quite slow but very little distortion if any of the panel on flat surfaces.

Not sure if they are still available - blades were replaceable.

R.
richard boobier

You can get a nibbler that attaches to a drill. Machinemart do them.
J White

Both of those will damage and shear the paint surface outside of the actual cut line, so I drill a pilot hole and then use a hacksaw blade to make the opening - and then take the last 0.5mm out with a hand file. That way I find the paint says intact right up to the edge.

Fergus

masking tape will help to stop chipping
cheers
R W Bowers

Any raduised courners use a hole saw ... i use an electric shear gun... not to expensive at your china mart discount tool store

prop
prop

Fergus do you have a side view of your wing vents ? They look good.
Dean Smith ('73 RWA)

I use a tiny air powered reciprocating saw with fine tooth blades.
Similar to this one:
http://www.eastwood.com/air-body-saw.html
Trevor Jessie

Wing vents may be a nice style feature, but for a road going car in the UK with a properly set up cooling system, l still think they are an unnecessary embellishment, really just for looks.
GuyW

Photos of aluminium vents as made off the timber former.

Fergus

another view

Fergus

and showing how effective they are in keeping the car cool

Fergus

Fergus

THATS exactly what im looking for... did you make those?

Prop
prop

Looks like they were formed on a wood buck. If you use "half-hard" aluminum it works well.
Trevor Jessie

3003-H14 ... I do not remember the old designation.
Trevor Jessie

Treavor

Fergus does mention off a timber former... but i wonder if he used aluminum stock and sent it thur a roller stretcher/srinker esp to get that raisd roll lip around the parmeter

are you refering to the big healy 100s ... ive seen them but gez there expensive and cheaply made ... granted they do have the shape and style like fergus but there little more then tin foil in my opinion
prop

Apperantly this site has very nice wing vents that fit both the big healy 3000 and 100s

but i can not find a search bar to find them

prop

http://www.kas-kilmartin.com.au/toc.htm
prop

Fergus do you have any vents for sale?
Daniel Stapleton

Prop, check out this image...

Paste into browser:

http://www.kas-kilmartin.com.au/AH275%20Rally%20vent.JPG

Alternatively Ctl f will bring up a search window on the site, search vent.

Found the image but not a price.
P R Clark

It all came out of a flat sheet bought off EBay. I made a timber former out of an old bit of 40mm chipboard which served both sides. The aly was pinned and press formed into the aperture using a bit of steel tubing for the corner rads.The slots were then cut with an angle grinder and the louvres let in and secured with pop rivets.The aluminium was an offcut 600mm X 300mm X 1.5mm and cost about a tenner. Sorry I've got nothing for sale.
Fergus

Prop, you sandwich a sheet of aluminum between two the wood forms, then clamp together and hammer the aluminum down to the form. It is not terribly difficult if you use the right materials. I've made some dash trim pieces using a similar method.
Trevor Jessie

Thanks

Im aware of that type of work and played with it along time ago but never got close to the resultd that fergus got...

fergus thats some serious skillz ... how did you get the little raised ridge around the premeter.. thats why i thought it may have been mechainally rolled then bent into shape
prop

P R

can you pkst a pic... im on my phone and cant get the site to work very well



fergus.. how long did it take to make a pair ?


Thanks

prop
prop

I suppose making the former took about 3 hours, then press forming and rolling the aluminium together with the cutting and assembly another 2 hours for each one, so in total a days work.
Fergus

Here you go Prop...

Only taken me 17 hours to figure out how to do it.

The web site says they have them in steel & aluminium.

Cheers

Paul

P R Clark

Eeewwww...Not good.

i dont think i want to see the Moss or VB version if those are considard to be better

prop
prop

This thread was discussed between 20/04/2016 and 27/05/2016

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