sf bay '88 install renn-aire or griffiths?

[sacoffee]

Originally Posted by wwest

Why would you assume OP doesn't have the intelligence to sort through, say, marketing HYPE (snake OIL) vs fully encompassing, ALL, practical experience and perfectly logical, but unproven, theories?

Because I knew you'd post here since you're waiting to pounce on AC threads now that summers here

[fintstone]

Originally Posted by jittsl

...
So happy with Retroaire that I'm about to order a bunch of new components for the my current 84 with a 3.8 liter project. This project will use their evaporator and blower mounted in a Behr box in the smuggler's box, hoses and dryer along with a 993 condenser in the left front fender and a 993 compressor.

Please let usbknow how it works out. I am especially interested in their evap blower....they claim a huge increase in CFM.

[jittsl]

Originally Posted by fintstone

Please let usbknow how it works out. I am especially interested in their evap blower....they claim a huge increase in CFM.

Already using their evap/blower in the 69 & 70 and happy in both cases. More than happy with the quantity of cooled air (except, as mentioned above, in traffic). No way the AC is the same as what you get in a modern car but good enough to make the cars tolerable in crap weather. In the case of the 69 (the second installation) I installed into an original Behr case because I wasn't overly excited about the fit of the repro case they supplied - it works but not as sturdy as the original and the repro. doesn't quite fit as well.

[texas993]

Originally Posted by jittsl

So happy with Retroaire that I'm about to order a bunch of new components for the my current 84 with a 3.8 liter project. This project will use their evaporator and blower mounted in a Behr box in the smuggler's box, hoses and dryer along with a 993 condenser in the left front fender and a 993 compressor.

I am not sure I'd get too excited about the 993 components. My 993 AC is marginal in 95* plus days. My retro air system for my '85 has both the front and deck lid condensers. Cold air isn't an issue and the new upgrade blower actually blows air! It is a good set up.

I told Rock that he can create an improved set up for the 993 using my car as the test case!

[jittsl]

Originally Posted by texas993

I am not sure I'd get too excited about the 993 components. My 993 AC is marginal in 95* plus days. My retro air system for my '85 has both the front and deck lid condensers. Cold air isn't an issue and the new upgrade blower actually blows air! It is a good set up.

I told Rock that he can create an improved set up for the 993 using my car as the test case!

Thanks for the information. I've been contemplating using a second condenser mounted in the nose of the "RS" bumper. You may have helped make up my mind. My primary reason for using the 993 front fender condenser was to keep weight forward and to reduce heat load on the engine.

Just so we are clear, are you saying that the 2 condenser Retroaire system in your '85 is better than your 993's?

[RSTarga]

I've got the factory front condenser in an RS bumper, with no fan and it cools great on the move. Stuck in traffic, tolerable. I'm still on R12, with factory rear deck condenser too.

[wwest]

Originally Posted by fintstone

Please let usbknow how it works out. I am especially interested in their evap blower....they claim a huge increase in CFM.

More CFM will be useless unless the evaporator surface temperature can be kept at ~33F. If the evaporator temperature rises as the result of additional airflow NOTHING is accomplished. Except maybe some additional level of discomfort.

[jittsl]

[QUOTE=wwest;8142814]More CFM will be useless unless the evaporator surface temperature can be kept at ~33F.

What do you guess the evaporator surface temperature is in the current system I have installed? I hope you answered (to yourself) that you have no idea because I'm almost certain you don't. All I know (and all I stated) is that the system works as is.

Why would we now start discussing an issue that may or may not be an issue? To say that something won't help without something else (about which we know nothing) is about as valid as me saying the AC system won't work with elephants living in the blower box - it may be true but who cares?

[jittsl]

Originally Posted by RSTarga

I've got the factory front condenser in an RS bumper, with no fan and it cools great on the move. Stuck in traffic, tolerable. I'm still on R12, with factory rear deck condenser too.

Excellent to know. My fender mounted 993 condenser does have a fan so hopefully I'll even have AC in the traffic.

[wwest]

[QUOTE=jittsl;8142876]

Originally Posted by wwest

More CFM will be useless unless the evaporator surface temperature can be kept at ~33F.

What do you guess the evaporator surface temperature is in the current system I have installed? I hope you answered (to yourself) that you have no idea because I'm almost certain you don't. All I know (and all I stated) is that the system works as is.

Why would we now start discussing an issue that may or may not be an issue? To say that something won't help without something else (about which we know nothing) is about as valid as me saying the AC system won't work with elephants living in the blower box - it may be true but who cares?

My mistoke...

Should have said...

More CFM will be useless if the temperature(***) of the evaporator vane/fin surfaces rises in accordance with the increased airflow rate/volume.

More simply said, at the previous lower speed you had already reached the maximum cooling capacity of the system.

"Target" is 33-35F, low enough to provide maximum cooling absent freezing up.

[wwest]

[QUOTE=jittsl;8142876]

Originally Posted by wwest

More CFM will be useless unless the evaporator surface temperature can be kept at ~33F.

What do you guess the evaporator surface temperature is in the current system I have installed?

No guess, I can tell you with ABSOLUTE certainty that when you "set" for maximum cooling the "target" temperature for the evaporator vane/fin surfaces will be 33-35F

I hope you answered (to yourself) that you have no idea because I'm almost certain you don't. All I know (and all I stated) is that the system works as is.

Why would we now start discussing an issue that may or may not be an issue?

Any A/C technician will advise you of the importance of the matter.

To say that something won't help without something else

(about which we know nothing)

AHA! That explains a LOT!

is about as valid as me saying the AC system won't work with elephants living in the blower box - it may be true but who cares?

Fill in...

[fintstone]

I think we all knew that the goal is to get the evaporator as cold as possible without it freezing up. Seriously? Obviously, your post that he answered sarcastically did not refer to a target evaporator temperature, but rather, his evaporator temperature. Why must you do this in every AC thread? You help no one and only impress yourself.

[fintstone]

According to a thread regarding the Singer 911s, they have the 993-like unit with fans in both front fenders and the oil cooler is in the front bumper/spoiler.

[texas993]

Originally Posted by jittsl

Thanks for the information. I've been contemplating using a second condenser mounted in the nose of the "RS" bumper. You may have helped make up my mind. My primary reason for using the 993 front fender condenser was to keep weight forward and to reduce heat load on the engine.

Just so we are clear, are you saying that the 2 condenser Retroaire system in your '85 is better than your 993's?

Two things keep me from making that statement definitively. 1. I have not spent much time in the 911 with the new AC system. Only complaint is that I wish that there was more air coming from the side vents. But not much wire could possibly come out of those vents.

2. I haven't taken my 993 out in the heat much lately. I am not really that familiar with that car's AC system. I do remember that it doesn't cool all that well when it is warmer than low 90s in Texas. I do know that it is nowhere nearly as cold as my other cars: 90s Mercedes, modern GWagen and a 2000 Land Cruiser (coldest of all).

[aschen]

Originally Posted by wwest

More CFM will be useless unless the evaporator surface temperature can be kept at ~33F. If the evaporator temperature rises as the result of additional airflow NOTHING is accomplished. Except maybe some additional level of discomfort.

if adding more CFM drags the evap temp up, then by defintion the higher cfm blower has increased heat transfer out of the cabin. That is to say it is working in some capacity.

I installed the Griffiths kit (just the basic one) and I have been pleased with the results. The kit is absurdly complete. I think he includes zip ties!

[Bob Kontak]

Originally Posted by texas993

I just installed (myself) a retro-air kit in my '85 cab. Simply amazing.

This is interesting. Bear with my wind......

Last year a member e-mailed me offline about which system to go with. Charlie Griffith's stuff was included in the list along with the usual suspects for premium upgrades.

OK, so he goes with the cheaper option AND has it installed by a class A shop that folks rave about here.

Results were pathetic. Why? I think the install shop was in a rush. Due diligence was not performed. The poor guy wished he had 55 degree temps at the vents, it was that poor.

When you do stuff yourself, you are nervous, overly fussy, feeling awkward and you over work it. Triple check, etc.

It makes a big difference when YOU are totally anal about an install.

DO IT YOURSELF. IF you can even sort of handle a wrench and are patient, DO IT YOURSELF.

[Bob Kontak]

Originally Posted by aschen

I installed the Griffiths kit ..............I think he includes zip ties!

Yes he does. In the early days (back in the 50's) Charlie provided the loaf of bread wire ties with the paper around them. Hell, that's all that was available.

The he watched "The Graduate" and the whole "Plastics" thing sunk in deep. The rest is history.

Installed Griffith's "less than basic" kit in 98 or so. Sanden compressor and a couple of barrier hoses. I still get my 50 degrees in Ohio to this day with R-12.

[sacoffee]

Bob is right .... I installed a Frankenstein. System cobbled together from what I think is the best from each vendor of 911 AC parts. Flushed the system thoroughly, tested, vacuumed and charged myself. It is not hard work. I get 55 deg temps at full blast in Houston summers.

[texas993]

I had a great test of my Retro Air AC system today. 95* and very humid today. Sunny too. I drove about 40 miles in freeway, residential, stop and go, and everything in between. My system kept the interior of my car at 70*. The compressor cycled on and off about half the time. Vent temp was 40*. Fan speed 2. There were moments when I was too cold.

Yes, I can truthfully say that it is superior to my 993 factory system.

$2k well spent as well as about 20 hours of my time. I was very particular about the install. And was patient in filling with R134. It took 22 oz.

[jittsl]

Originally Posted by Bob Kontak

DO IT YOURSELF. IF you can even sort of handle a wrench and are patient, DO IT YOURSELF.

In confirmation of this - I did do this myself and was a little anal and was very happy with the results.