Getting cool air into the footwells

[Frankenhealey]

Anybody have some good ideas apart from power sapping aircon?

Cheers,

Ian

 

[andybj8]

Ian

I believe Cape do an uprated fan kit ref kfk2, I believe it uses a 4" inline fan that goes in the duct, you will need to check with Steve, otherwise why not double up and get a modern 12v 4" fan.

andy

 

[Frankenhealey]

Andy,

Ducts have gone. They're behind the new firewall needed to bring it up to race safety specs.

Cheers,

Ian

 

[Cottontop]

Hi Ian,

Before my current mods, I had a duct from the radiator support into each footwell.

Airflow was controlled by a small pull-knob on the outer corner of the dash connected to a butterfly valve.

NOW, I have Air Conditioning with a valved duct that dumps cool air into each footwell.

Tim

 

[AUSMHLY]

Tim,
No Demisters?
Heater?

"NOW, I have Air Conditioning with a valved duct that dumps cool air into each footwell."
You installed an actual air conditioning unit?
Must be nice :cooler:

 

[HealeyPassion]

Ian, the a/c takes a few hp when on... but I doubt that there is much parasitic loss when it's off. Just a thought.

Cheers,
Steve

 

[Cottontop]

Hi Roger,

No Demisters? Heater? You installed an actual air conditioning unit?

Since I installed the Ford V8 in 1976, I have not had a heater nor demisters (NOR a top, but that's another story....).

Remember, I have a Healey, I have a V8, and I'm in Texas. ALL 3 of those conditions make a heater unnecessary.

Yes, I have installed an actual A/C unit (not just open windows). When you have 300 HP, you can spare a few to be COOL ! It even has a built-in heater, although it'll probably never be used.

It hangs from the cowl webbing, between the back of the instrument panel and the firewall.

Must be nice

Not finished modding yet, but I'll let you know.

Tim

 

[Patrick67BJ8]

Ian, the a/c takes a few hp when on... but I doubt that there is much parasitic loss when it's off. Just a thought.

Cheers,
Steve

My AC when ON is barely noticeable. The Factory AC and it's York compressor was another story but the rotary fits and operates real smoooooooth. I suppose I could wire the throttle and AC through the OD throttle switch to kick off under full throttle(with a time delay for reconnecting), but the 5 speed took care of that mod. A fast idle solenoid is now needed so I'm reseraching that.
Patrick

 

[dougie]

Ian I've ran an air duct directly from my rally vent to the footwell of my vintage racer. The only problem is if I don't cover it while competing in the rain.

Dougie

 

[Cottontop]

The only problem is if I don't cover it while competing in the rain.

dougie,

It's a duct.... There's a tAPPe for that !

Tim

 

[Michael Oritt]

Dougie--

How do you fill those reservoirs?

 

[dougie]

Michael - They're not quite as tight as they look. Given the fact I usually overflow my morning coffee (my wife always lets me know) I do pretty good topping off the reservoirs.

Dougie

 

[Frankenhealey]

Steve,
No room for an A/C compressor under hood so Ive had to rule that out in the past.

Tim, Dougie,

I want to draw cool air into the footwells and exhaust it from there. If I blow cool air into the footwells I'm going to get all the warm air around my face. I like Tim's pictures of the footboxes with the piping so may put a couple of inline 12V fans there and exhaust out of the wing vents.

Thanks for all the sage advice.

Cheers,

Ian

 

[Michael Oritt]

"Given the fact I usually overflow my morning coffee (my wife always lets me know)"
------------------
Well my wife always lets me know that I can't hit the toilet while standing up and thinks it reasonable that I be required to pee from a sitting position. I tell her she is simply jealous that I have options but that never seems to get much of a laugh.

 

[Cottontop]

If I blow cool air into the footwells I'm going to get all the warm air around my face.

No matter WHAT you do, you are going to get the footwell air in your face.

Air ALWAYS moves from a source of higher pressure to a place of lower pressure.

Because of the airflow hitting your windsheild and flowing around both sides (and over your hardtop) the fast moving air will create a low pressure area in the cockpit and suck the air out and into the flowing airstream. Think of someone smoking a cigarette in the car ahead of you with the window open a bit. Almost all the smoke is sucked out the window.
Bernoulli's Principle

If you bring or force (fresh) air into your footwells, it will move from that higher pressure area around your feet, up into the lower pressure area around your shoulders and head, to be sucked out the side window openings or top vent.

The ONLY way to keep that from happening would be to TOTALLY seal the side windows (and THAT ain't gonna happen with a Healey) or to construct a cockpit tonneau that ties tightly around your neck. Then you might be able to vent the footwell air out of the side vents and keep it outta' your face.

I want to draw cool air into the footwells and exhaust it from there.

Sorry Ian, but I don't think that will work. If you duct fresh air into the footwells, I don't think that you'll be able to use even high CFM fans to try to suck it out of the footwell before it has a chance to ascend into the low pressure area around your torso. The footwells are a huge volume to try to evacuate with fans.

IF you are able to successfully evacuate the air from the footwells, the footwells then become a low pressure area, probably lower than the upper cockpit and I'm sure that the air will move down from the cockpit faster than it will come in through the fresh air footwell vents. That might keep the footwell air out of your face, but if that happens, there would be no need to duct fresh air from up front into the footwells.

Several companies make 12-24 VDC ELECTRIC A/C compressors. Then put the A/C in the trunk/boot. Might be worth a look-see.

See what Pete thinks?

Personally, I like the sight picture of the necktie tonneau :thumbsup:

Tim

 

[Cottontop]

I wanted to add that since I had fresh air vented footwells, I speak from experience.

The effect of having a flow of ambient air on your feet & legs FAR, FAR, outweighs the effect of having that slightly warmed air move up around your shoulders and face.

Of course, I had no hard or soft top. I had so much air coming and going all over the place that I hardly noticed the footwell air.

Tim

 

[RAC68]

Hi Ian,

Recently, I completed an article that addressed a way of supercharging the air stream of the cold air vent through the use of a speed-controlled 4” bilge blower. Although the installation is relatively hidden and produces a selectable (with the use of a DC speed controller) volume of air (up to 240CFM), it is not air conditioning.

All the best,
Ray

 

[Lin]

Ray,
Where do we find the article?
Lin

 

[Keoke]

No room for an A/C compressor under hood so Ive had to rule that out in the past.

Well Ian, if you use one of the modern compact compressors there is plenty of room to install one under the hood and its operation will not feel like someone is hanging on the rear bumper.--Fwiw--Keoke

 

[Michael Oritt]

Lin--

Go here to see a page from the West Marine catalogue for a 4" inline bilge blower:

https://www.westmarine.com/webapp/wcs/sto...mp;ci_sku=34108

Mounting it should not be very difficult.