Yet another aircon upgrade thread

[SimonN]

Yes, I know, this keeps coming up and I have read all the other threads. But summer is coming (hopefully) so having got the heating working, it's time to think about cooling. I thought it might be worth starting another thread as I have questions not answered in other threads, and it might motivate a few others (group buy???)

So for those new to the subject, the definitive thread is

 The Upgrade Aircon Thread

Based on this thread and my research, I am about to order a kit from Retroair (Retroair kit ). The question is, what "extras" do I need? I have just received the following quote (all in US$).

Base kit                                   1455.00

Blower upgrade                       195.00

Front condenser                      199.00

Front condenser fan upgrade  179.00

Shipping                                   404.19

That makes a total of US$2432.19 or AU$3227.76, plus import duty, GST etc, which will probably add about $400.

What i am struggling with are the "extras". My car is very much a "second" car - if it gets really hot, I don't need to drive it. I am after a system that will be effective up to, say, about 32 degrees. I want to get away from the situation I had with the RS which meant every time the temperature got over about 24-5 degrees, i questioned whether i needed to use it. i know some would say that is soft, but please don't come back with suggestions of winding the windows down or getting a soft top or any of the other shit like that (I guess that guarantees those responses!)

So I would love to hear from those who have done the upgrades and get a view of how far I need to go.

And if anybody is interested in a "group buy", pm me and I can see if we can get a deal.

[michel]

Simon speak to SM911,  he installed a system in his partners car. They live in Brissie . It's icy

[bumble]

Looking forward to the various inputs here.  My SC was UK delivered and spent most of its time in NZ so never had need for AC.  Different story here!  Looks like Retroair's advertising is about right - appears to be the only one to offer a complete package.  In the others I've looked into, they want you to acquire separate doo-dads and spend time modifying stuff which I'm not interested in.  May also be interested in a group buy if there's sufficient interest.

[Russ]

Coastr on here has also made the stock system work properly, and has a lot of knowledge 

[SimonN]

Coastr on here has also made the stock system work properly, and has a lot of knowledge 

That is the other option. I am not after a meat locker, just a comfortable environment for driving on an "average" day.

[Russ]

I should actually say 'better than stock'

[P-Kay]

@Coastr the collective PFA airless community await your invaluable feedback! 

[Steve88]

Do you want the Autohaus Hamilton kit price. 

Mine goes in next week

I looked at all the options and felt it was the best piece of kit around. Especially when you look at price , frieight and the quality of components

[P-Kay]

Apologies if I am speaking out of turn @Simon Nelson, but I for one am interested in components and cost from @Steve88

 

[Coastr]

Well I'm not sure I would go that far to say it is better than stock.  What I did was take the stock system, which already had a rotary compressor upgrade and do a diagnostic check and filled it with Hychill which is a hydrocarbon (bbq gas + butane + secret sauce) mix.  

I used it most of the way back from NSW on the weekend when it was a mild and pleasant 25 degrees outside but made it nicer to drive with the windows up and cool air for the sun coming in directly through the glasshouse.  Even though the air temp is not hot, there is not enough airflow ina 911 just using the demister vents - the original design had little 1/4 windows and pop out 3/4 windows - once this disappeared you're stuffed in terms of getting airflow with the windows up.

when it gets to 27/28 degrees it still works ok and when it gets to 32/33 things are not as rosy - it still keeps the cabin pleasant on the highway but it won't cool down the car if heat soaked and not so great in heavy stop/go traffic.

After a lot of reading and research this would be the way I would go:

- if you have a stock system or parts of a stock system,  I would get it vacuum tight and gas it up and see what you get.  If it is still r12 you can try a Hychill drop in replacement gas instead of experimenting with r134a.  You can tell r12 by the type of connector - r12 looks like and old bike valve and r134 has the push collars.  You'll be looking to check your compressor clutch engages , your condenser fan (front) works, and blower fan interior works, and that the system can hold pressure.

- if you have nothing then the retro air or the Griffiths kits are the way to go.  I wouldn't try and recreate the stock system from parts.  Seems as though Griffiths is very thorough and will want to get involved to ensure you are successful, this may or may not be a good thing, depends on your perspective.

- in terms of upgrades I can't give personal experience but from reading endless threads about it the main areas to concentrate on are condenser area and internal airflow.  Th stock vents in pre-86 cars are a joke and the blower motor has too slow, not quite right and hurricane speeds.  So you want more condenser surface area and more airflow over the condenser, then you want to move more air in the cabin itself.  I would really be stumping for the upgraded versions if I was putting a new kit in, but probably wouldn't bother if I had some stock bits left over (assuming they were serviceable)

in terms of installation and charging up etc two years ago I knew zero about this but just read up and bought a vacuum pump, manifold pressure gauge and oil fill and a box of o-rings.  Since then I have done a few different AC repair jobs and it's really not that hard, but if there is anyone from the industry reading they will be spitting chips about 'backyarders' and danger and generally making a fuss.  So what I have done so far is illegal and I am a bad, bad person.  Probably the hardest thing is sorting the wheat from the chaff and wading through all the FUD generated.  

so in terms of the OP - I would buy once cry once and buy that kit and have a go at getting it all installed yourself if you're a spanner twirler.  You can leave the gassing for a professional or have a go yourself.

Ultimately if you keep the car for two summers you'll have gotten back the value in spades.  And you'll improve the resale value as well, because unlike RWB wings or Magnus wheels, everyone loves AC.

[SimonN]

Do you want the Autohaus Hamilton kit price. 

Mine goes in next week

I looked at all the options and felt it was the best piece of kit around. Especially when you look at price , frieight and the quality of components

I didn't know that the sold it as a kit of parts. i thought you had to get it installed by them and I want to do the work myself, both to keep costs down and because I enjoy it. I am certainly interested in knowing more, how much and what you get.

Thanks to Coastr. I think you have crystalised 2 things. First, I need to test the current system although I am not that hopeful because, while it seems that it has know refrigerant which will make some difference, the fins on both the evaporator and rear condenser look a bit bent to say the least. there is also a lot of evidence of past efforts to make it work. The other thing I realise now is the comment about how bad the blower is and therefore I think this is worth replacing.

[Steve88]

Autohaus Hamilton Kit 

$675 Inc Serpentine type rear wheel well condensor with 12' fan

$325 Inc Parallel Flow main engine lid condenser

$325 Inc 3 sp Blower motor with larger fan and base plate

$290 Inc Serpentine type evaporator core and TX Valve

$690 Inc Sanden Compressor and CNC Aluminium adapter plate.

$35 Inc Conti V belt

$2340 Inc GST Total

Plus $90 freight to Melbounre. This doesn't include the lines as Darren from Autocoupe is making them for me which adds about $1750 including lines , re-gas and install off the top of my head 

[Coastr]

I have damaged condenser fins.  Unless all of them are damaged its probably not that big a deal.  It is surface area that matters over total airflow I think.   Even if fins are bent they are still exchanging heat.  It is low speed large volume air movement going through the rear condenser.

i just bought a vacuum pump off eBay - at about $150 it's the same price as a single appointment with a mobile aircon guy.  Having a vacuum pump allows you to test whether you have big leaks in the system.  You also need the gauges which again can e had for cheap.  The professional guys don't like to work with cheap crap but for a total life time use of < 10 times its no big deal.

so if you're thinking about working with the stock system to see what you get and want to diy that would be my first move - pump and gauge set.  Even if you end up going full retrofit kit you'll still get use out of them.

[Steve88]

Also if all those components are made in the US for your OS kit there should be no import duty. 

[SimonN]

i just bought a vacuum pump off eBay - at about $150 it's the same price as a single appointment with a mobile aircon guy.  

I have just spent the last 20 mins pricing vacuum pump and gauges vs getting a recharge done! I have come to the same conclusion.

[turboT]

 

http://www.carsales.com.au/cars/results?q=(Service%3D[Carsales]%26(Make%3D[Porsche]%26(Model%3D[911 Carrera]%26Series%3D[964])))&area=Stock&vertical=car&sortBy=TopDeal&WT.z_srchsrcx=makemodel

 

[Peter M]

I know you don't need to buy 964 or a 993 to get useful air conditioning in an air cooled car.

It's been almost 3 years since I fitted a Retroair upgrade kit to my factory fitted '85 and can say it still works a treat and I am still happy with the time and money spent.  There is a caveat however!  I never drive in heavy traffic so the poorer air conditioning performance that is evident at slow speeds is not a concern.  On the open road however I find the lowest fan speed and turning the thermostat up to make it less cold the norm.

 

Probably the only comments I can make are:

• Don't underestimate how important vent size and air flow is.  I fitted Duel Kuehl's on mine to supplement the two standard centre vents but if I was doing mine again I would consider converting the two centre vents over to fresh air only (using predominately standard parts identified in the PET) and installing 3 or 4 discrete under-dash vents.  If you have a '86 onward car you can ignore this.
• Don't just replace everything blindly.  Depending on it's condition and what level of performance you want I think there is plenty that can be reused if the condition is OK.
• I think these should be far more popular: http://www.allzim.com/store/911-cool-air-kit-1.html  If you car already has a complete system, plumbing in an extra condenser in the rear mudguard plus a new safety switch (or tri-switch to operate the condenser fan as well) and new receiver dryer may be all you need. 
• Anyway you cut it, they need one reasonable sized condenser with a good sized electric fan. 
• If you have a Tea Tray spoiler, you're lucky as there is room above the condenser to have a useful sized electric fan.  Us less flashy ones with Whaletails or no tails at all will struggle to find fans to fit underneath.
• Most of AC parts are generic and can be bought very cheaply if you use Google to identify the part numbers.  Buying readymade "911" solutions is convenient but you pay for it.
• Take 15 minutes and make up a fused harness for the front blower fan.
• There is not necessarily one solution fits all.  I'd install a different system in a hotrod 911 to what I would a good resto car where the market obliges you to stay pretty close to standard.  If I was doing a hotrod I would start looking at the Vintage Air catalogue for ideas.

 

 

      

[Steve88]

I know you don't need to buy 964 or a 993 to get useful air conditioning in an air cooled car.

It's been almost 3 years since I fitted a Retroair upgrade kit to my factory fitted '85 and can say it still works a treat and I am still happy with the time and money spent.  There is a caveat however!  I never drive in heavy traffic so the poorer air conditioning performance that is evident at slow speeds is not a concern.  On the open road however I find the lowest fan speed and turning the thermostat up to make it less cold the norm.

 

Probably the only comments I can make are:

• Don't underestimate how important vent size and air flow is.  I fitted Duel Kuehl's on mine to supplement the two standard centre vents but if I was doing mine again I would consider converting the two centre vents over to fresh air only (using predominately standard parts identified in the PET) and installing 3 or 4 discrete under-dash vents.  If you have a '86 onward car you can ignore this.
• Don't just replace everything blindly.  Depending on it's condition and what level of performance you want I think there is plenty that can be reused if the condition is OK.
• I think these should be far more popular: http://www.allzim.com/store/911-cool-air-kit-1.html  If you car already has a complete system, plumbing in an extra condenser in the rear mudguard plus a new safety switch (or tri-switch to operate the condenser fan as well) and new receiver dryer may be all you need. 
• Anyway you cut it, they need one reasonable sized condenser with a good sized electric fan. 
• If you have a Tea Tray spoiler, you're lucky as there is room above the condenser to have a useful sized electric fan.  Us less flashy ones with Whaletails or no tails at all will struggle to find fans to fit underneath.
• Most of AC parts are generic and can be bought very cheaply if you use Google to identify the part numbers.  Buying readymade "911" solutions is convenient but you pay for it.
• Take 15 minutes and make up a fused harness for the front blower fan.
• There is not necessarily one solution fits all.  I'd install a different system in a hotrod 911 to what I would a good resto car where the market obliges you to stay pretty close to standard.  If I was doing a hotrod I would start looking at the Vintage Air catalogue for ideas.

 

 

      

can you elaborate on point one about air vents size ? Is it a particular brand you got Duel Kuehl's I've never heard of where can I find it   ?

[Peter M]

From the "definitive" (!) thread: 

Anyway, at an ambient temperature of 24C yesterday at a steady 100kph I was getting a air vent temperature that cycled between 4 and 7 degrees C as the thermostat turned the compressor on and off.

 

Today being hotter (28-30) this morning and idling around town doing errands with much less airflow through the main condenser gave a vent temperature of 7 to 10 degrees C. I would not have even considered driving this car previously in similar conditions but was comfortable with the AC on.

 

The more powerful evaporator fan works a treat but being an '85, the size of the "slit" side vents are still a limiting factor and increasing the airflow is now the next obstacle to improving comfort.

 

Maybe a pair of DuehlKuehl vents for Christmas?

https://griffiths.com/product/duehl-kuehl-vents/

 

[Peter M]

Oh, forgot to say the Autohaus Hamilton kit warrants a closer look and might well be better value than Retroair.

[Coastr]

From the "definitive" (!) thread: 

 

https://griffiths.com/product/duehl-kuehl-vents/

 

those would make a difference.  I tend to drive by myself and point both centre vents at myself.

pricey though, for what they are.  I guess small production run.

[OZ930]

From the "definitive" (!) thread: 

 

https://griffiths.com/product/duehl-kuehl-vents/

 

Rock supplied one of these vents with my kit but  I didn't use it.  I didn't realise they were so expensive.  You can buy similar vents for $1 or $2 each then buy some vent hose to suit.

I "reinstalled" my AC with a RetroAir kit, which replaces all the inefficient pieces with modern more efficient parts and looks like factory. To improve low speed air flow I fitted a thermo fan to the rear condenser.

I also wired in an isolate switch, which turns off the compressor and condenser fans but allows the evaporator fan to blow air from the centre and side vents. Better cabin non AC air flow.

The switch has an internal light which  illuminates when the compressor and fans are cycling on.

BTW: the air temp coming from the centre vent is 1.5 degrees C.

[Peter M]

They were pricey for what they are but they were ready to go. Having cool air on each side of the dash helps a lot. 

I recall Vintage Air sell identical ones much much cheaper and you can still buy the corrugated paper and foil lined air vent tube quite cheaply from Porsche for that "factory" look!

 

[Peter M]

Brian,

When was the last time you bought vents for $2?  1972? 

 

I think Summit sell something similar for about $16USD each or you can buy them locally for about $38AUD each.

Nevertheless a good addition as a concentrated blast of cold air from the centre vents only isn't the most comfortable. 

[SimonN]

So I am coming up with a plan.

I am going to start with the current system. I will check it for leaks and recharge it, probably with HyChill minus 30. If all is good with the lines, I won't replace them because the cost of the gas to recharge means that I would need to recharge something like 9 or 10 times before I am behind the game. I think that will be over 20 years and that assumes I don't need to recharge the new hose system in that time. Of course, if there are any leaks or problems with the hoses, that is another matter. I will also check everything else is working, such as the front condenser fan.

After checking the temperatures achieved by the existing system, I will be looking to make some modifications. I think the first thing to do, irrespective of temperatures, is to add more vents and get a better blower.

Then it will be a case of getting extra cooling if needed and there I am torn. I can see how the rear wheel well condenser and fan would be a quick win, but I personally would prefer a system that looks like the original (am I being too dogged about that?). For the same money, you could buy a new, upgraded main condenser and evaporator. And if i start adding or changing components, I guess it makes sense to change the receiver/dryer.

So what are the flaws in this plan?