I "WWested" my 84's a/c system

DaveMcKenz · 03:28 PM

Hi guys,
I know many of you have opinions on WWest's a/c advice. While I don't agree with everything he says, I think he does make some excellent points.
I have a full Retroaire system that i installed last year. New hoses, compressors, heat exchangers, fans; everything. It still did not perform as well as any cheap modern car with a/c. I have decided to enhance my current system with several of Mr. West's suggestions:
I have tinted windows (already had them.)
I have back dated heat with SSI's, but I reinstalled my engine fan which now blows (a lot of) air out the bottom of the engine bay.
I added two 8" puller fans that come on with the a/c clutch. They run off a relay and separate fuse. They each pull 2.8 amps and 1600 CFM.
I don't have a trinary switch (I do have a r134 high/low switch).
I also have a California Pop Top which is a white Tyvek partial car cover, to help keep the car from overheating while parked in the Sun.
Here's a picture.
We will see how it works in a few months when our Chicago weather goes from cold to hot.
Thanks for looking,
Dave

DaveMcKenz · 03-07-2015, 01:06 PM

What made me go the fan route was my research into the 964 a/c system. It uses a single front wheel well condenser with a 10" fan that really pulls a lot of air. This single condenser is smaller than our deck-lid condenser yet it cools very well. Admittedly the 964 evaporator and blower is probably better as well. I decided that maybe we don't have inadequate condenser area, but we really have inadequate condenser air flow. I am not the first person to think this, and Mr. West is probably not the first either. Anyway I had a couple of fans lying around, so I mounted them up. They just barely fit, and they do not have a proper shroud, but they probably cover 50% of the condenser.
We'll see how they work.
Dave

Jrboulder · 03-07-2015, 01:44 PM

Interesting, I just received my full retroair kit and I'm working on installing it. I have my engine compartment blower hooked up to a switch so I'm going to see how it works to pull extra air. Where did you get this California topper?

DaveMcKenz · 03-07-2015, 01:54 PM

I used the wrong name for the car cover. It's a California Pop Top sold at capoptop.com. In anther car I owned which was dark green, the inside temps would be 140 on a 90 degree day, parked in the Sun. With the cover, it would be the same as the outside temp. No greenhouse heating.
Dave

Jack Stands · Jack Stands's Garage

Hey Dave,

Looks nice and it will be interesting to see how it handles the heat and humidity (once we get done with this winter). It looks like you're having the heater fan in the engine compartment simply fed without the air ducting from the driver's side engine duct. I like the look without all the extra ducting if it blows enough air through the SSI heat exchangers.

DaveMcKenz · 03-07-2015, 01:58 PM

Hi Jack,
The engine fan just sucks air through the condenser and blows out on the ground. My heat is dependent on the shroud fan, and footwell blowers to move air through the heat ducts.
Take care,
Dave

Bob Kontak · Bob Kontak's Garage

Quote:

Originally Posted by DaveMcKenz

Hi Jack,
The engine fan just sucks air through the condenser and blows out on the ground.

Isn't the engine kinda sorta sealed?

DaveMcKenz · 03-07-2015, 02:41 PM

Hi Bob,
The engine compartment is indeed sealed, and that's good. However, there is a sealed hole in the engine tin where the electric engine compartment blower discharge duct passes through to get to the heat exchangers. When you backdate the heat, usually that hole is eliminated, and indeed the whole electric blower and duct too. I decided to leave the blower in place along with its discharge duct, and the sealed hole. This lets the blower suck air in through the condenser, and blow it out on the ground. The SSI heat exchangers only get air blown into them by the engine cooling shroud main fan. I also have foot well blowers to boost the heat flow.
Dave

Bob Kontak · Bob Kontak's Garage

OK - different than the SC. You have an "out". Cool.

tirwin · tirwin's Garage

Is that a stock condenser?

DaveMcKenz · 03-07-2015, 06:51 PM

Quote:

Originally Posted by tirwin

Is that a stock condenser?

That is the Retroaire parallel flow condenser. I think it could be done with the stock one as well. There are also lower profile fans than I used.
BTW I am skeptical of their 1600 CFM rating, but they do move quite a bit of air.
Dave

tirwin · tirwin's Garage

I was just curious because it looks very different from mine.

Clearance in the engine bay is going to be a variable for others. In my '83 if I have the coil sitting too far up in the mounting bracket it interferes with the condenser, so very little room to work with. Your engine bay looks like it has a good bit more room. I am seriously considering going to a 3.6 and I've been told I might have to eliminate the decklid condenser if I do.

Good luck with the project.

ganun · ganun's Garage

Hi Dave, I am in Miami and so far the full RetroAir kit has not needed added fans, even in traffic, but certainly added fans can't hurt. My comment would be to add the trinay so that the extra fan turn on only when necessary, maybe even staged.
In my 87 I found the oil temp getting uncomfortably high even though it was cool inside while in traffic so I lowered the oil cooler blower temp switch setpoint. Like you though, have to wait until summer to test it.
BTW, I see you went with the Nippondenso I went with the Sanden.
Cheers,

ganun · ganun's Garage

I didn't mention that I put headers and removed all heater components, fwb included, and made a blanking plate to cover the hole in the engine tin. Your solution to use the hole is what I would have done.

Discseven · Discseven's Garage

Clean engine Dave... compliments. Am interested to see what vent temps you get come summer. Will you say what weight of 134 you loaded?

jittsl · jittsl's Garage

Just as a thought. I added neoprene around the condenser and rubber seals around the trunk lid to force all air through the condenser. The top one is my 911 - which because it has PMOs has no room for a fan and the lower is my 912.

DaveMcKenz · 03-08-2015, 10:49 AM

Thanks Laurence, I already have seals on the sides, but may add on top and bottom.
BTW I was not happy with the zip tie type fan mounts as a definitive mounting, so I made an aluminum bracket to add mechanical support.
I cleaned up the wiring a little bit too.
Take care,
Dave

wwest · wwest's Garage

Quote:

Originally Posted by ganun

Hi Dave, I am in Miami and so far the full RetroAir kit has not needed added fans, even in traffic, but certainly added fans can't hurt. My comment would be to add the trinay so that the extra fan turn on only when necessary, maybe even staged.
In my 87 I found the oil temp getting uncomfortably high even though it was cool inside while in traffic so I lowered the oil cooler blower temp switch setpoint. Like you though, have to wait until summer to test it.
BTW, I see you went with the Nippondenso I went with the Sanden.
Cheers,

Instead of adding a trinary switch you could tape and insulate one of these to rear lid condenser inlet fitting. Don't know what temperature "trigger" level to suggest, some experimentation is due.

Strange as may seem the heat exchange process become more efficient the greater is the differential between the two mediums. Plus, not need to run the blower/fans unless there is a need.

DaveMcKenz · 03-08-2015, 11:56 AM

I like that switch, and may try a couple of different temps. Anybody got a recommendation for temp at say the inlet pipe of my condenser. Or maybe it should be at the outlet of my condenser?
Thanks,
Dave

wwest · wwest's Garage

Improve CFM by 50%

And another point in favor... Cabin heat level no longer varies with engine RPM.