Keloges,
I insulated as much as possible....had to take some off to get the lid to close, the blower housing is bigger than stock,See pic.
http://forums.pelicanparts.com/uploa...1369171973.jpg

Here is the new evap.
http://forums.pelicanparts.com/uploa...1369172034.jpg

About the tunnel, I forgot about all the lines that go thru, each with a grommet, I replaced both fuel lines and that was not fun, there are also e brake cables, shifter, hyd clutch line, accel rod.... plus the sheetmetal gets warm if not hot back there. It does not seem to me a good area to draw air from. I`d like to hear reasons why it should be kept. I am tempted to stuff some foam into the tunnel ahead of the shifter and behind the pedal area to minimize air from the rear.
Pic of the hole near the drivers foot.
http://forums.pelicanparts.com/uploa...1369172554.jpg

The ""normal" air intake.
http://forums.pelicanparts.com/uploa...1369172785.jpg

Thanks all!

ganun,

I don't believe I would say/said that was Porsche's design, however logically if you cap off
either intake more air (though restricted now) would pull in from the other side.

You WANT both intakes open and you WANT all of your ac vent outlets open.

Better to be lucky. I bought a sweet , bone stock '88 911 Coupe with an upgraded to r134 refrigerant system in November. I ran the a/c monthly as recommended in the factory manual (always my bible) to keep the system lubricated. The New England winter temps gave me no sense of whether it was working. Recently as the climate warmed up it was clear my system was just blowing stale tepid air. Had to be worse for me than anything I could dump into the environment. I read all the doomsday threads here on DIY re-charging. This forum is my guide for most DYI procedures. After 10 P cars through the years I figured why change my ways now. Went to Autozone, bought a r134 recharge kit with the oil already added and a pressure gauge. I am a carbon footprint kind of guy. Followed the directions, leaked a little poison and destroyed some more atmosphere along the way to raise the system up to the advised lower end of the pressure level. (did wear the safety glasses and gloves) It has been blowing cold and as the manual says performs best at higher RPMS. For how long I have no clue. I married a Virginian and a/c is part of the south's birth right. She says it is good a/c, likes to drive the car and so we will just enjoy my daily driver.

George I have a lot to say regarding what you just posted with pictures of your evaporator and I will

But let me quickly say before I post a more detailed reply about it.

Let me say this first; you want the whole black plastic box and covering outside "COMPLETELY INSULATED"!!!

I do not like The black foam insulation you are using, it’s too thick and the density of the foam material I think needs to be much more denser, also as you have found out due to its thickness you had to remove some of it.

Also from your pictures I do not see any insulation on every part of your lower plastic evaporator box

Let me give you a better idea

The silver aluminum and rubberized sound proofing material that is sticky backed adhesive you are using in your pictures for your floor area etc is a really "good insulation material" we would probably use it for insulating the evaporator box and cover if it were black colored; so if you have some left over you should think of using it on your evaporator for insulation; then the foam insulation you are attempting to use, also note this silver type of sound insulation is a thinner material then the back foam; as you have discovered is too thick for complete coverage.

Note The spray type expanding foam you can buy at home depot for example would be really good insulation due to its foam density but it’s too difficult to work with for the outside the evap. box. But I do used it sometimes on the Inside of the evap box VERY CAREFULLY to fill air for better evaporator air flow control and insulation


BTW We use a either black rubberized cork material or an even better material Stokes found that is about 1/8 inch or so in thickness for the outside of the plastic evap. box

Hi Keloges,
Thank, appreciate your input but I did this about a yr ago, if I have to take it out for what ever reason I will do a more seamless insulating job. FWIW, the factory didn`t bother with ANY insulation anywhere, so I thought any is better than none! I did the whole floor and firewall (F &R) with Dynamat and Dynaliner, which is the material on the evap. It was $$ so I tried to use it all up.
http://forums.pelicanparts.com/uploa...1369234870.jpg

I also lined as much of the interior of the smglrs box, one thing that I didn`do that I wanted to but in the assembly just got carried away was to sheath the plastic COLD air ducts all the way to the dash vents....oh well, what would be a good material????
http://forums.pelicanparts.com/uploa...1369235207.jpg
Thanks
George

Mr. Thomas did a very nice write up on upgrading his AC. In this thread:
Insulating the evap box
Although this client insulated his box, 99% of our clients do not insulate
the box and have excellent performance.

So, insulating the box in theory is logical however its 'what ever floats your boat'
as they say.

An easy way to get more airflow is to get a 3" boat bilge air fan, cut off the mounting tabs, and jam it into the air intake opening - it's a tight fit and it will stay there by itself. Then wire it into the 'high' setting of the fan using a relay, and 'boom' 20% more cool air (made up number) for around $30...

I did this to mine, as a stop gap until I can build a real air box with a monster SUV sized fan - really happy with the results for now, and yes it all fits behind the floor board (note I have the rennlist floorboard).

Chuck.H
'89 TurboLookTarga, 352k miles

As far as I am concerned all serpentine design heat exchangers are obsolete !!!

Note All automotive OEM major manufacturers generally have abandoned serpentine technology including Porsche Factory products several years ago for oil coolers, a/c condensers and evaporators! The older technology has been replaced by newer heat exchangers technologies that are now 30 to over 50 percent more efficient; and at least 25 percent or more smaller in dementions

I really like it that all my early model 9111 competition still clings to old technology ways of thinking and products. <grin>

Don’t get me wrong, serpentine technology works, however so does Model T technology too, But the world of technology moved on a long time ago. Today and in the future it is extremely challenging to stay up with the advancements of new state of the art technologies!

My NEW TYPE 911 EVAPORATOR using newer Parallel Flow Evaporator Technology that has slightly smaller dimensions then is currently available for early model 911’s but even FAR more efficient, I redesigned and successfully tested last year and have been sitting on; It will have installers choice, either FOR (TX) “Thermal Expansion Valve”, or even THE more efficient (VOV) “Variable Orifice Valve & an additional (needed for orifice valves) receiver tank installed before the compressor return inlet” ???

This year I have another state of the art new Parallel Flow Plate & Fin Evaporator Technology redesigned prototype for 911s that is wider and perfectly fits the full width of the early model 911 black plastic evaporator case; that is also shorter in length then the OEM 911 evaporator. But I am not releasing pictures of it at this time.

My mind is always thinking of invention and engineering new things to play with; NOTE: this same technology heat exchanger for this 911 evaporator prototype in the picture I posted; I have also been thinking about turning it into another product for state of the art high tech 911 Oil Cooler heat exchangers after looking at the aftermarket DIY Oil Cooler markets.

http://forums.pelicanparts.com/uploa...1334060035.jpg

NOTE: TIPS & TRICKS THE RETANGULAR PLATE is an enhancement that fits inside Smugglers box plastic evaporator container to further fully control the evap incoming CAB air below the evaporator, air sealing and enhance the air vent blowers output colder over originally done by Porsche, and when this evaporator is installed onto this special plate the evaporator is recommended to be further completely sealed by blocks and/or liquid expanding or other internal foaming sealing, together with the added outside of the plastic evaporator case being further coated and sealed together with enhanced exterior insulation material

http://forums.pelicanparts.com/uploa...1334060217.jpg

http://forums.pelicanparts.com/uploa...1334060853.jpg

NOTE: Bottom evap is the latest 911 serpentine design currently available for 911s, I consider "serpentine OLD obsolete technology;" compared to my upper pictured evaporator with far newer plate & fin more efficent and my PFC's technology for 911s[/QUOTE]

Howdy Chuck,

cool your in FL too

I am very familiar with all the 3" boat bilge air and other types of uses fans like you’re talking about, I even bought one last year probably like you are talking about I thought might use for my 911 front hi tech PFC condensers I have designed. I had had the same thinking you just wrote about here.

To let you know I am a marine mechanical engineer and I work on super yachts for many years, but when I was young I first started on small boats and yachts, and it causes you to learn TO THINK OUTSIDE THE BOX compared to other industries to say the least

I have another type HIGH SPEED and CFM coaxial 3 inch type fan I bought last year after doing a lot of technical research that is just over an inch thick or so, and when I get around to it I will post a picture so you can see what it looks like and also post all the tech data about it, however its not made or used in boats; but it’s 12 volt dc and claimed to be water proof

I also have a couple of other fans I found last year I will post pictures of too, these would be good for the front condenser mounted to the ground under side etc

George Dynamat also comes in black!

I could not remember its name when I told you to call Stokes Automotive and ask him what he uses for evaporator outside insulation. Black Dynamat is perfect for this

Intresting idea Chuck,
I like it, but then the topic of this thread comes up, i.e. if you don`t block off the round hole to the tunnel, you can`t pressurize the bottom side of the evap box like I think was/is your intent. A good fan at the inlet under the floorboard will blow air out by the drivers right foot. See the picture above, in the pic you can see the hyd clutch line junction thru the hole and part of the opening which unfortunately is not very obvious.
I'll keep that fan idea in mind though, together with the doing something with the tunnel.
Keloges, that evap sure seems to have a lot more surface area, so thats the latest tech now????

Yea, I used Dynamat and Dynaliner ( no Al , just hi dens sticky backed foam)

George your evaporator will work good for you, especally the great way your installing it
on your 911

what is most important for your a/c components are your condensers

What are you using for condensers?

George what part of Miami do you live in?

Serpentine is not obsolete. lol. Actually condenser design mfg's started fabrication of PP
units 16 years ago because they are "cheap" to build. I have a PP stock/factory coil in my 2005 Touareg, its falling apart already, the material is simply too thin as compared to serpentine. A large bug can damage the coil.

Noooo... that is a competitor's copy or our first revision model built 10 years ago.
Our Serpentine Rev 4 blows them all away.

Did you know that "plate and fin" evaporators, alike the one you are playing with,
introduced in the Boxster and 996 around 1998 are now failing! As well as
all other cars using the same plate and fin designs. Once you figure out why
feel free to chat.

I blocked off the round hole the last time I had the evap out, before I thought of this modification. I am fully sold on the idea of MORE AIR and will be building a new air box shortly, possibly with twin squirrel cage blowers - if they over drive the evaporator at least I can turn them down and have 'mo air and less noise.

Chuck.H
'89 TurboLookTarga, 352k miles

The stock front, and new serpentine that came in the kit for the rear. This Sat there is a car / air show at Tamiami airport (Kendall off the tpikr), noon to... Come on down !
Its starting to get hot so its a good tome to test the a/c.
The local Alfa club was invited so I'm taking it and the 911.

Kuehl, could you tell us a bit about the Gen 4 evap, taller, more fins?
Curious.
How about a material for sleeving the cold air distribution hoses?
George

ganun,

The Retroaire rear condenser doesn't span the complete opening of the decklid. I fabbed some end pieces out of some aluminum treadplate to close the gaps to maximize flow through the condenser. Just something for you to consider.

http://i906.photobucket.com/albums/a...asyover/c2.jpg

[/QUOTE]

Your "new" evaporator looks exactly, and I do mena EXACTLYU, like the one for the early series LS400, 1990-94. Something stuck along the "bottom" in the pictures indicates that it may have at one time been installed in the same upright position.

And a word of caution along those lines..The tighter the "weave", the more dense the vanes/fins are, the more likely it is that condensate will remain within the evaporator, viscosity/capillary effects overcoming gravity. Then in our Porsche's you add the effect of the blower moving (holding) condensate against gravity and you may well end up with a water filled "sponge" blocking ALL low speed airflow.