'87 911 A/C Upgrade - "Progress"

[CBRacerX]

I spent some time preparing the rear decklid to receive the condenser. I went with JB Weld holding on AL brackets. I used a fairly large base for the brackets and drilled holes in them to give the two part epoxy a good chance to grip the metal. The factory condenser has brackets that were easy to match up to on the rear. On the front I added some angle which will have a foam strip ala the factory retention method.

[tsuter]

I put a single big ass condenser up in my turbo tail. Mounted it to the deck lid so the tail slips over the top.
Couple of puller fans activated off the trinary switch and done.

Condenser was 28.5" x 15". So really big! No secondary condensers at all.





There's a whole thread on how to do this. Get 30Fs' at the vents. Doesn't sell much product though like underbelly, front mount or wheel well condensers.......

[CBRacerX]

Here are some images of the rear condenser for Jeff at Rennaire:

[CBRacerX]

More progress to report. Cleaned out my old factory rear condenser using an air driven cleaning bottle and acetone (this is the only original part of the plumbing left). Rennaire finished modifying the 993 compressor connections by welding new crimp on hose ends to the factory hose adapters. I used my new crimping tool to connect the lines and got the two way Ho-Lo switch plumbed in. The two way sensor allows for conventional hi-lo compressor cutoff and the operation of an auxiliary condenser fan relay for the rear if you are so inclined - I am saving this for a future upgrade path if needed. I also plumbed in the procooler. When I went to pull a vacuum on the system I found that my ebay gauge kit did not include the correct fittings for r-134a type hose ends. Bummer. So while I wait for the adapters to arrive, the system is only a leak test and charge away from a functional test. Finally!


2 way Hi-Lo


Welded adapter


Insert hose and crimp!


Rennaire did a nice job with this





EBay AC tools


The hoses tuck into the tail and engine compartment fairly well, although they are not pretty


Took this setup for a spirited drive and so far no tire interference issues

[CBRacerX]

After a false start using a poorly made r-134a charging adapter I got my system charged a few minutes ago. I will let the pictures tell the story:


Charging Setup established. Off camera is a very large shop fan blowing on the rear condenser. I did not raise the rpm above idle during the charging and measurement process.



Ambient Temp.


Quantity of r-134a added (lbs and oz). This was on the low side of what Rennaire recommended and I left this as a starting point and will real world test it later today.


Hi and Low side operating pressures. Also seem on the low side.


High Side to front condenser


High side to compressor


Compressor case temp


And the money shot - Center vent temp with stock fan on "II"

[pete3799]

Nice.
Only trouble is you'll need driving mittens.

[CBRacerX]

Originally Posted by pete3799

Nice.
Only trouble is you'll need driving mittens.

LOL - As a Vermonter you are familiar with this. Good problem to have, I hope

[JFairman]

This is how I positioned the procooler in my 930.

I have 235/40x18 front tires and I need as much tire clearance as possible.
The procooler installation up the page a ways wouldn't work on my car because the tire would grind up the hose during left turns in no time.

You can see where my left front tire rubs the inner fender well at full left lock sometimes.

[CBRacerX]

I have been driving for a while with the p-cooler in this location and no problems - BUT I am only using 7.5x17 wheels with 205's up front. Track tires could expose something bad and when that time comes I will look carefully

EDIT: What may not be clear from the pic is that I put the canister as high as possible in the wheel well. So high that I could not clamp it to the facotry attachment and the line from the evaporator is in a potentially bad position. But so far all is well.

[CBRacerX]

I have taken a long drive with the AC on and it works like a charm! Yet to remove the bow-tie and replace with something that lets me direct this air, but using the stock (large) vents on the '87 provided real comfort with my all black interior. So color me "cool blue" and satisfied for now! Still a ToDo for the wiring of the Hi-Low switch and perhaps a revisit of the measurements with Rennaire as a sanity check.

One result of this effort is that I am now somewhat stocked up in the garage to work on basic AC systems. This is the tool list I accumulated:

• Serious Vacuum Pump (ebay)
• Ho-Low Gauge Set and manifold (ebay)
• Additional Hose for refrigerant tank to gauges with valve (ebay)
• Set of r-134a to r-12 hose adapters (ebay)
• Solvent "blaster" cleaner (ebay)
• Vent thermometer (ebay)
• Digital Refrigerant Scale (ebay) - this will be useful in many garage projects as it handles over 200 lbs
• r134a tank to r-12 adapter (ebay)
• Manual hose crimping tool with three dies (ebay)
• 30 lb tank of r-134a (Coolgas.com) this had to ship from unregulated TX to PA since I do not have the correct paperwork to buy from a PA dealer

So did it cost more than just taking the system to be charged at a professional? You bet. But I love tools and always seem to find a use for them later after the "last" project is done. If local Pelicans need to borrow these the offer is out there.

[mthomas58]

Well done. Congrats on your results and your new tool stash

[CBRacerX]

Originally Posted by mthomas58

Well done. Congrats on your results and your new tool stash

Thanks. I'll repeat my offer for local Pelicans - these tools are available if you find yourself needing them.

[Joeaksa]

Chris,

One year on, how do you like the system? Any changes you would make.

My only suggestion that would change is I have an 85 model and my vents are not as big as yours, so while in there would try the PerformanceAire mod and drill another opening for cool air out into the car. As small as the earlier vents are on the dash feel that it would be needed.

Glad you are open to loaning your tools. I have basics (gauges and vacuum pump) and loan them out to local friend who I know are trained on using them.

Joe A

[CBRacerX]

Originally Posted by Joeaksa

Chris,

One year on, how do you like the system? Any changes you would make.

My only suggestion that would change is I have an 85 model and my vents are not as big as yours, so while in there would try the PerformanceAire mod and drill another opening for cool air out into the car. As small as the earlier vents are on the dash feel that it would be needed.

Glad you are open to loaning your tools. I have basics (gauges and vacuum pump) and loan them out to local friend who I know are trained on using them.

Joe A

More air (if it is cool!) is always good. I probably will remove the bowtie and maybe even drill another hole down there. But other than that, no changes needed!