a/c in model a ford

[Jack B. Roarke]

information on ken davis a/c for Model a ford

[Jason in TX]

http://www.kendavismodela.com/

To contact Ken Davis:

817-540-1513
[email protected]
[email protected]



It works well.
You can install it yourself in your driveway with free rental tools from Autozone.
It doesnt rob the engine of noticable horsepower.
You can remove it if you sell the car or need to go back to stock.
It makes your wife happy to ride with you on trips.
The better you insulate the floor and firewall, the cooler you are.
For just over a grand, it's not worth the hassle in making the brackets yourself and buying all the parts separately.

[Jason in TX]

[Pilotdave]

I have been wondering about this system! I'm curious as to why it doesn't use engine hp. Also wondering whether it puts additional burden on the water pump bushings. Thanks!

[Jason in TX]

I does use 2 or 3 horsepower, but it's really not noticeable when it kicks on and off. I guess it is due to the torque of the Model A engine.

I would recommend getting a leakless style pump with one of the sealed front bearings. Or get whatever kind you want, but get one with the front sealed bearing. They can handle more load. Mostly because you need to get that belt tight on the alternator.

[Pilotdave]

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Interesting! Thanks, Jason.

[MrTube]

It only uses 2 or 3HP? Most automotive systems were upwards of 6-8HP no?

Does it use a TXV or fixed oriface? Is that a variable displacement compressor?

[azmodela]

Originally Posted by MrTube

It only uses 2 or 3HP? Most automotive systems were upwards of 6-8HP no?

Does it use a TXV or fixed oriface? Is that a variable displacement compressor?

Most of the old systems and compressors used six or more horsepower. The new ones only use one to three horsepower as mentioned. Efficiency in compressor design helps!

[Franchise_24]

Air conditioning for me is opening up the front window with the other 2 down Cummon, do you really need AC in a Model A!!?!?!?!?

[MrTube]

Originally Posted by azmodela

Most of the old systems and compressors used six or more horsepower. The new ones only use one to three horsepower as mentioned. Efficiency in compressor design helps!

I am unaware of modern systems in cars being more efficient. R134A systems produce a far higher head pressure than R12 systems did under the same conditions. This means they use more power and it also means greater stresses on the pump and its seals.

The only improved efficiency I am aware of is the popular use of TXV's combined with variable displacement compressors. However on a very hot day (95-105F) these systems still consume A LOT of power especially when not moving fast.

[Jason in TX]

Originally Posted by Franchise_24

Air conditioning for me is opening up the front window with the other 2 down Cummon, do you really need AC in a Model A!!?!?!?!?

It was 107 in Conroe Tx this past weekend for the Texas Tour. Guess how hot the wives feet and legs get on top of that riding above the exhaust? Rolling down the windows just makes it a windy oven.

I went to a junk yard here in South Texas once that was full of late 40s and early 50s cars. Of 30 cars that I poked my head in, about 22 of them had add on A/C units that were probably done in the early 60s. They thought cars needed them then as well.

What I'm getting at is YES. Model As are much more pleasant to drive in Texas with A/C.

You northerners put heaters in your cars. They didn't come with heaters. I would say in January when I drive my car I don't need a heater. A jacket is warm enough. Also with your heaters, You have to cut holes in your firewall.

With this A/C system you can add it and then remove it and put the car back to stock without a visible sign of it ever being there.

[Jason in TX]

Mr Tube? Im aware that your other hobby is old refrigerators and refrigeration units.

Have You driven a Model A with an A/C unit? All I've said is that you don't notice (seat of the pants dyno) the car loosing speed or power when the compressor turns on. Can an accurate engine dyno pick up in power loss? Probably. Does the sweaty driver and passenger notice horsepower reduction or power consumption when the inside of the car goes from 101 degrees to 75 degrees? Not at all.

[Franchise_24]

Originally Posted by Jason in TX

It was 107 in Conroe Tx this past weekend for the Texas Tour. Guess how hot the wives feet and legs get on top of that riding above the exhaust? Rolling down the windows just makes it a windy oven.

I went to a junk yard here in South Texas once that was full of late 40s and early 50s cars. Of 30 cars that I poked my head in, about 22 of them had add on A/C units that were probably done in the early 60s. They thought cars needed them then as well.

What I'm getting at is YES. Model As are much more pleasant to drive in Texas with A/C.

You northerners put heaters in your cars. They didn't come with heaters. I would say in January when I drive my car I don't need a heater. A jacket is warm enough. Also with your heaters, You have to cut holes in your firewall.

With this A/C system you can add it and then remove it and put the car back to stock without a visible sign of it ever being there.

Nope, no heater for me. I do see your point about 107 degree weather tho. I've had my share of hot days in the Coupe, I've seen upwards of 95 to 97 I think and it does get warm. To me the only cure is driving to get the wind blowing lol.

[MrTube]

Originally Posted by Jason in TX

Mr Tube? Have You driven a Model A with an A/C unit?

No Sir,

My responses are only in regards to power consumption not whether or not you should have one in an "A".

I'm a person that hates heat so much I learned how to maintain and build my own refrigeration systems so believe me I would never be against installing one in any vehicle or building

Perhaps the system is much smaller than I originally thought. Comparing the compressor size to the alternator it does appear very small.

Just out of curiosity Jason, do you know how many BTUs that system is capable of?

[MrTube]

Jason,

Instead of only questioning what you had said I should have also made the comment that I thought the installation was very interesting. I like it.

The condenser under the rear of the car is also very creative.

[Jason in TX]

Ok. I'm getting you now. You like the science behind it. Hey, I don't work for Ken Davis or anything, but now I'm having to research power consumption and BTU performance of the systems that another person sells.

I'm glad that if I review a restaurant that I like, I don't have to tell the person the amount of calories I ate, the temperature at which the chicken Cordon Bleu was cooked, and the grams of butter used in the recipe. I just say it tasted great! But we are Model A fanatics and that is a different story.

Good thing I like digging on the internet for information, but Ken better cut me a deal on my next A/C unit after all this work!!! (Photoshop, pictures, graphs, data charts. shwew! Tough crowd!)



A/C only (HEAT UNIT ALSO AVAILABLE) evaporator unit designed to mount under the dash board. The evaporator has four round louvers. The controls are located in the center of the unit. The evaporator has a three speed blower motor with a dual fan setup. The evaporator unit has passenger side hose outlets, the fittings for the hoses will be on the passenger side of the unit when it is installed. The evaporator has approximately 290 CFM and 14000 BTU. The evaporator unit is compatible with R-134a and R-12 refrigerants.
The evaporator unit includes:

• Three speed blower motor
• Adjustable temperature thermostat
• Evaporator unit mounting hardware
• Expansion valve
• Drain tube & cork tape for hose fittings
• Orings
• Two rubber grommets

The evaporator unit measures: 17" wide x 12" deep x 5" tall




BELOW IS THE PERFORMANCE OF THE COMPRESSOR: "COP" I BELIEVE MEANS "COMPARISON OF PERFORMANCE" BETWEEN REFRIGERATION CAPACITY AND POWER CONSUMPTION. THE FLATTER THE CURVE, THE MORE EFFICIENT THE COMPRESSOR IS ACROSS RPMS. I REQUESTED THIS MODEL OF COMPRESSOR AND THIS IS WHAT IS IN MY CAR CURRENTLY. BASED ON AVAILABILITY, THERE ARE OTHER MODELS OF COMPRESSOR THAT HAVE ALMOST IDENTICAL PERFORMANCE CURVES. IF YOU LIKE RESEARCHING DATA, LET KEN KNOW WHAT EXACT MODEL NUMBER COMPRESSOR YOU WANT AND HE WILL WORK WITH YOU.

Compressor Specifications
Bore - ø35
Stroke - 28.6 mm
Displacement Per Revolution - 138 cc/rev
Number of Cylinders - 5
Max. Allowable Continuous Speed - 6000 RPM
Max. Downshift Speed - 7000 RPM
Refrigerant - HFC134A
Oil - (SP-20 or Equiv) 175 cc
Rotation (Clutch View) - Clockwise
Clutch Specifications
Rated Voltage - 12V / 24V
Breakaway Torque - 3.5 KG-M
Minimum Engagement Voltage - 7.5v Max / 16v Max
Power Consumption - 42~50W (AL / CU)
Max. Allowable Continuous Speed - 6000 RPM
Max. Downshift Speed - 7000 RPM

[Fred]

QUESTION, What did people do in Texas or any where else for that matter when it got "HOT" back in the day with any Model "A", Not drive it ??.. I doubt it !!

[Jason in TX]

That's kind of a silly argument.
"They did it then, so that's the way it should always be done now."

What did people in the North or any where else for that matter when it got 20 inches of snow on the ground back in the day with any Model "A", Remove the gas and coolant, put it on jackstands in their garage or barn and not drive it for 5 months??? .. I doubt it!!


Technology today allows us to bolt a device on our cars that will keep us 30-40 degrees cooler when we drive it, and if we want to remove that device, you just un-bolt it.

Cars only had one tail light from the factory. Do you add a second tail light and a 3rd brake light, or just go with the 1 tail light because they did it in 1931 so it must be good enough for now. Seat belts.... they hadn't started putting those in cars in 1930.... That logic could go on and on.


The basic issue here is someone asked how the modern A/C units work in the Model A. I replied "They work well." and then I provided data to show their functionality.

I didn't say, "We should all hot rod our cars and throw away history."


I think I'm going to go out in the garage and fix my original starter switch on the bone stock 6 volt Vicky now. I could upgrade to a starter solenoid but the original Henry Ford way works just fine.

[Fred]

YUP, Don`t forget to open the windows, It might get hot with out A/C...

[MrTube]

Jason,

Sorry for being a pain

Looks like that compressor consumes around 4HP at 2000 rpm and as high as 5.3HP at 3000rpm. Not sure what RPM it spins on the A but I guess its moot.

4-5HP is a small price to pay to be comfortable and as I said I love the install.


In response to Fred's comment, QUESTION, what makes you happy when you drive your model A? If its A\C then by all means put it in!. If its a high compression head, high performance cam and overdrive, put it in!.

If its driving a 100% STOCK model A then that is exactly what you should do. Each person has their own opinions and thats how it should be.

[Jason in TX]

No problem at all MrTube. I enjoy doing the research and learned more about the system in the process. I actually spoke to Ken today and I joked around with him about posting the info!

[azmodela]

The compressor consumption shown in the chart posted by Jason is measured in kW, which is also a metric horsepower measurement. That's different than the mechanical horsepower that you're trying to compare it to. One metric HP is the equivalent to 1.3 mechanical HP which would put it at 2.6 HP for 2000 compressor rpm and 5.2 at 3000 compressor rpm. A rule of thumb is the compressor turning about half of the engine rpm. That of course varies on systems, pulleys and other things. They can get even lower with some of the systems mentioned, look into the compressor draw on cars like Civics, Prius, and other for 1 to 2 hp draws.

[Tom Wesenberg]

Now I get it............it's all these modern cars with air conditioning that is causing global warming!

[Fred K-OR]

Originally Posted by Franchise_24

Air conditioning for me is opening up the front window with the other 2 down Cummon, do you really need AC in a Model A!!?!?!?!?

Me too, I thought the A/C was the open front window. You either open it one notch or all the way. Maybe that is bad for the ladies hair!

All kidding aside, great report on A/C.

[Jason in TX]

Not going over 72 degrees for the next 10 days in Banks Oregon?
Sounds like beautiful Model A'ing weather!!

[Logan]

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Originally Posted by Jason in TX

Not going over 72 degrees for the next 10 days in Banks Oregon?
Sounds like beautiful Model A'ing weather!!

haha and it's suppose to be above 95 for the next seven days here in the dfw metroplex. People just dont understand how hot it really is in an A in texas. Once you add in outside heat, plus heat coming from the engine compartment and exhaust. Inside the car it easy reaches temps breaking 100 degrees and it kills you while sitting in traffic, with no air to blow threw that open front windshield and windows. A/C allows people to tour in their A's all year long in texas and other hotter southern states. Plus you have to add in the health factor, some of the older people in the clubs need the A/C so they can keep driving their cars longer.

If you dont want an A/C in your car, dont put one in it. problem solved. jmho

[John Duden]

Originally Posted by MrTube

Jason,

Sorry for being a pain

Looks like that compressor consumes around 4HP at 2000 rpm and as high as 5.3HP at 3000rpm. Not sure what RPM it spins on the A but I guess its moot.

4-5HP is a small price to pay to be comfortable and as I said I love the install.


In response to Fred's comment, QUESTION, what makes you happy when you drive your model A? If its A\C then by all means put it in!. If its a high compression head, high performance cam and overdrive, put it in!.

If its driving a 100% STOCK model A then that is exactly what you should do. Each person has their own opinions and thats how it should be.

I second that, what ever makes you happy, Just go with it. Wether it is putting on a accesory, or cutting the frame or different wheels, Or how much you spend on a part, it is yours and it is to fit your will,

I am installing rear shock asorbers in my early 28 truck, i am going to use two out of a 95 ford f350 so it rides nicer and does not bounce or shake the truck apart
Just my 2 cents
John

[40 Deluxe]

If efficient, affordable add-on A/C were available in 1930, there would have been A's lined up for blocks waiting to have it installed! (At least if it weren't for the Depression!)

[CarlG]

Originally Posted by 40 Deluxe

If efficient, affordable add-on A/C were available in 1930, there would have been A's lined up for blocks waiting to have it installed! (At least if it weren't for the Depression!)

What cost $1000 in 2010 would cost $70.53 in 1931.

[MrTube]

I have to agree with fordgarage on this one. I drove a 92 chevy c2500HD which had a gross weight of 8600lbs for years and the shocks in the rear were unbelievable. I could never see putting them in any kind of car or even a light truck.

Would they even fit under a model A? They were like 4 or 5 inches in diameter.

One time I had a dumb moment and tried to impress a friend with a burn out. I popped the clutch in 2nd gear and the wheel hop ripped both shocks out of the frame. Never did it again.

[John Duden]

ours rides really nice, maybe becuase dad made his own bed for the back, and it is really heavy, and they will have more resistance on them
John

[CarlG]

Originally Posted by Fred

QUESTION, What did people do in Texas ... when it got "HOT" back in the day with any Model "A...??...

Look up Air Conditioning on the Sacramento Vintage Ford site:

[azmodela]

Originally Posted by Logan

haha and it's suppose to be above 95 for the next seven days here in the dfw metroplex. People just dont understand how hot it really is in an A in texas.

I think I understand. I'll take your "above 95" over our temps any day.

[Fred]

I guess my POINT is, you have only a little H/P to start with, Then we add A 12v. Alt. extra lights etc. Now we add an A/C unit that WILL use more H/P.. But we still have that little radiator & very small (SO CALLED WATER PUMP).. Can they hold it ?? @ 107 ? What`s next, Lets add Power steering on the other side... Next ?? on Fordbarn will be, I cant understand why I have NO power on hills & it gets HOT real QUICK !!.. How can I fix It ??... Its your car go for it...

[CarlG]

One advantage you have here is that the condensor is no where near the radiator, so it's not adding heat there like in a modern car.

[Logan]

Originally Posted by Fred

I guess my POINT is, you have only a little H/P to start with, Then we add A 12v. Alt. extra lights etc. Now we add an A/C unit that WILL use more H/P.. But we still have that little radiator & very small (SO CALLED WATER PUMP).. Can they hold it ?? @ 107 ? What`s next, Lets add Power steering on the other side... Next ?? on Fordbarn will be, I cant understand why I have NO power on hills & it gets HOT real QUICK !!.. How can I fix It ??... Its your car go for it...

I believe there are over 500 of ken davis' a/c units are in use today all around the world. So he's doing something right. I'm a very close friend of ken's and have watched him make dozens of these units while visiting with him. Yes you have to have a good radiator to be able to use the units, but in texas or anywhere the weather breaks 90 degrees consistantly everybody that drives their cars has a new modern core in their radiators. And the 3 Hp that it takes to run the compressor, you wont feel the difference in the performance. Needless to say i am impressed with kens unit, and everyone that has one loves it. I just ordered mine last week to put in the sedan, and i will be sure to report how it works when it is installed.

[TinCup]

I can imagine that this unit would run you out of a coupe in a heartbeat. My cousin in Melissa, Tx. has one of Ken's units in his Fordor and wouldn't be without it. A smaller blower unit would be a nice touch. These blower units look like the ones I had in my 63 implala.

[48Ratfink]

Rumer has it that Fred is going to purchase an a/c unit afterall! I mean why else would He spend so much time on this thread!!!

[Fred]

BAD Rumer !!.. Would not put one in either of my cars if you gave me one.. P.S. It was 97 here yesterday & very HUMID.. My 28 Coupe & I were just fine with the windows open..

[Franchise_24]

Originally Posted by Fred

BAD Rumer !!.. Would not put one in either of my cars if you gave me one.. P.S. It was 97 here yesterday & very HUMID.. My 28 Coupe & I were just fine with the windows open..

I'll second you on that. But like someone else said, to each their own. I'd never have one, but if someone else wants one, more power to them.

[MrTube]

I was without A\C in my daily driver for all of 2 months before I snapped and said enough is enough. Sitting in dead stopped traffic every day in central NJ on 90+F days listening to 5+ other peoples music was just too much for me.

[Wide Whites]

I think Jason has convinced me to put a/c in my roadster!! Can I cut holes in the seat and run vents to the rumble seats? Just kidding Jason! I want to look into a/c if/when I get a fordor!

let me know if you could use an extra hand when you install a/c in the vicki. I'd like to see how it goes so I can do it down the road.

[48Ratfink]

Its been bordering 100 here and I also roll down My windows and ride with a big smile!

Originally Posted by Fred

BAD Rumer !!.. Would not put one in either of my cars if you gave me one.. P.S. It was 97 here yesterday & very HUMID.. My 28 Coupe & I were just fine with the windows open..

[Pilotdave]

Been doing some research on power consumption given my concerns (another thread) about poor performance of my Tudor which runs a 6v 30a alternator.

IF (big "if") I have it right, a 6v generator putting out 10a would consume about 0.12 hp [7.2v x 10a, 20% efficiency loss, 746 watts/hp]. A 12v alternator putting out 60a would consume something a tad north of 1.6 hp. [14.2v x 60a, 30% efficiency loss.] A 6v 30a alternator would consume about 0.4 hp. So there is a hp price to pay for switching from Henry's generator to an alternator. What's unclear is whether that price is large enough to matter (to those who would choose to go this route) in terms of performance penalty.

Happy to have someone check my math and theory - this is definitely not my area of expertise! And thanks to those above who posted similar material.

[dmaxweb]

Originally Posted by TinCup

I can imagine that this unit would run you out of a coupe in a heartbeat. My cousin in Melissa, Tx. has one of Ken's units in his Fordor and wouldn't be without it. A smaller blower unit would be a nice touch. These blower units look like the ones I had in my 63 implala.

ditto on a smaller blower unit. can't give up the leg room.

[Jason in TX]

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Originally Posted by TinCup

I can imagine that this unit would run you out of a coupe in a heartbeat. My cousin in Melissa, Tx. has one of Ken's units in his Fordor and wouldn't be without it. A smaller blower unit would be a nice touch. These blower units look like the ones I had in my 63 implala.

I run one in my cabriolet, the same cabin space as a coupe and the biggest struggle with the unit is how insulated you can make your vehicle. You see, the unit is taking the ambient air from around your feet and the firewall, pulling it into the under-dash unit via "squirrel cage motors" blowing that warm air across the evaporator coils (small icy cold radiator inside the blower unit) and out into the car.

If you feed the unit 100 degree air, it has to cross the cold coils and cools the air down to 80. But what is supposed to happen is that now 80 degree ambient air that is in the car passes across the coils agian and cools it down to 70 degree air.

If the car isn't insulated enough, or the toe board or firewall isn't insulated enough, you continue to struggle with cooling really warm air. So the key to comfort is in how well your car can keep the heat out.

Adding the plastic molded firewall insulator that Snyders and Brattons sells is a great idea, or some people go to home depot and purchase outdoor carpet that is almost an exact match to the carpet sold by Lebarron Bonney for our cars. Making a carpeted firewall, with some foil or jute insulation behind it is very helpful. Also the exhaust manifold having the heat shield over it is of additional help.

If you made the motors smaller, or the unit smaller, you are in essence reducing the effectiveness of the unit. And due to the fact that our cars have a gas tank as our dash, this can't be hidden behind it like our modern cars have. Guaranteed that your Honda, Chevy or Ford has a larger evaporator and fan than this hang down unit has. It's actually very small and efficient already. Also, there is plenty of leg room still as well.

[MrTube]

Jason,
I believe many 1970s-1990s cars had air conditioners that were in the neighborhood of 28,000BTUs. It is not easy to cool a car off as you stated even when they are insulated. Plenty of glass on all sides and on newer cars you must have some fresh air circulation. Obviously 28,000 BTUs is NOT a small unit by any means.

I like the idea of mounting the unit on top of the car in a cylindrical shaped enclosure painted white . Hmmmmm.

[Jason in TX]

You are on to something!!!

Heck, just remove the top insert and put the monitor top on there instead. Generator on the luggage rack.

You'll have the coldest head and shoulders in town!! Work it right and you could make it snow inside the car during Christmas time!