AC upgrade progress
12-27-2005, 01:56 AM
#1
Three Wheelin'
Thread Starter
AC upgrade progress
I am in a slow process of upgrading the AC in my 930 -- replacing the old-tech tube and fin condenser and evaporator with high-tech multiflow condenser and serpentine evaporator, plus new drier and barrier hoses.
One of the few AC specialists with products for Porsches -- Retro-Air -- happens to be near me in Dallas. He offers a kit for the normally aspirated 911 with a full-width multiflow condenser, but for lack of a development car he had no 930-specific kit. With my 930, he now had the car so we have been working together to develop the kit with the differences required for a 930.
It's mostly customizing the fitting of a high-tech multiflow condenser and associated plumbing to the confines of half the 930 tail and sizing the right length of the hoses that go from the tail to the front. The rest is the same as the standard 911. Fitting the 14x14 condenser wasn't too difficult -- I was able to adapt it to the factory mounting points. The challenge was the plumbing from the compressor to the condenser. The inlet is in a different place than the stock tube and fin condenser. On my '89, the factory connection used a custom bent tube running up the right side of the deck hinge. '88 may have done this too but it seemed prior years just bent a hose around the hinge. I didn't want to do that. To make a long story short, after much trial and error, I finally found a custom AC tube fabricator near Dallas who custom bent a tube exactly to my specs. It's now on computer so can be reproduced.
Retro-Air is having the brackets I made recorded for reproduction and laser cut. I spent several hours this weekend carefully removing all the hoses and the evaporator assembly from the smugglers box. We'll be verifying the hose lengths shortly. The serpentine evaporator already exists as well as the other parts, so now that everything is removed, when the new brackets arrive and hoses are made, the kit will be complete and a slow, careful install will commence. I also plan to do some cleaning as long as I'm "in there" and restoration or replacement of the plated screws and brackets (there plating looks kind of crappy after 16 years) plus replacement of disintegrating foam to make the installation look and function like new. I will also be installing an infinitely variable fan speed control to replace the current 3-speed fan. This should solve the problem of speed 2 being too low and speed 3 too high.
Compared to the incredible engine and mechanical work others on this board have done, this isn't much but I think the results will be good. Only factory mounting points are used and the kit should be a nice direct replacement. I don't get to do much of this mechanical work and am busy so I only get to do a few hours a week. A couple of pics of the dismanteling follow.
1 - the beginning
2 - old condener left vs. new right
3 - how the new condenser and hard line will fit but with better brackets
4 - two hoses going to the evaporator
5 - the tangled mess of the 911 AC system
6 - the evaporator and blower in the smuggler's box. The flexible hose connecting the blower to the vent tubes was a bitch to get off. Not looking forward to replacing it.
7 - successful removal -- disintegrating foam will have to be replaced.
One of the few AC specialists with products for Porsches -- Retro-Air -- happens to be near me in Dallas. He offers a kit for the normally aspirated 911 with a full-width multiflow condenser, but for lack of a development car he had no 930-specific kit. With my 930, he now had the car so we have been working together to develop the kit with the differences required for a 930.
It's mostly customizing the fitting of a high-tech multiflow condenser and associated plumbing to the confines of half the 930 tail and sizing the right length of the hoses that go from the tail to the front. The rest is the same as the standard 911. Fitting the 14x14 condenser wasn't too difficult -- I was able to adapt it to the factory mounting points. The challenge was the plumbing from the compressor to the condenser. The inlet is in a different place than the stock tube and fin condenser. On my '89, the factory connection used a custom bent tube running up the right side of the deck hinge. '88 may have done this too but it seemed prior years just bent a hose around the hinge. I didn't want to do that. To make a long story short, after much trial and error, I finally found a custom AC tube fabricator near Dallas who custom bent a tube exactly to my specs. It's now on computer so can be reproduced.
Retro-Air is having the brackets I made recorded for reproduction and laser cut. I spent several hours this weekend carefully removing all the hoses and the evaporator assembly from the smugglers box. We'll be verifying the hose lengths shortly. The serpentine evaporator already exists as well as the other parts, so now that everything is removed, when the new brackets arrive and hoses are made, the kit will be complete and a slow, careful install will commence. I also plan to do some cleaning as long as I'm "in there" and restoration or replacement of the plated screws and brackets (there plating looks kind of crappy after 16 years) plus replacement of disintegrating foam to make the installation look and function like new. I will also be installing an infinitely variable fan speed control to replace the current 3-speed fan. This should solve the problem of speed 2 being too low and speed 3 too high.
Compared to the incredible engine and mechanical work others on this board have done, this isn't much but I think the results will be good. Only factory mounting points are used and the kit should be a nice direct replacement. I don't get to do much of this mechanical work and am busy so I only get to do a few hours a week. A couple of pics of the dismanteling follow.
1 - the beginning
2 - old condener left vs. new right
3 - how the new condenser and hard line will fit but with better brackets
4 - two hoses going to the evaporator
5 - the tangled mess of the 911 AC system
6 - the evaporator and blower in the smuggler's box. The flexible hose connecting the blower to the vent tubes was a bitch to get off. Not looking forward to replacing it.
7 - successful removal -- disintegrating foam will have to be replaced.
12-27-2005, 10:35 AM
#3
Burning Brakes
A/C is on my to do list after the engine is complete. I was thinking of using the Griffiths parts: http://www.griffiths.com/porsche/ac/911ac/index.html with the condensor in the left rear wheel well, but then a friend suggested just doing a single under body condensor. I've been leary of using the underbody condensor due to risk of damage, but he made the point that the underbody condensor is cheap compared to the others so even if it's damaged it's not that big a deal.
12-27-2005, 10:44 AM
#4
Drifting
Originally Posted by 125shifter
A/C is on my to do list after the engine is complete. I was thinking of using the Griffiths parts: http://www.griffiths.com/porsche/ac/911ac/index.html with the condensor in the left rear wheel well, but then a friend suggested just doing a single under body condensor. I've been leary of using the underbody condensor due to risk of damage, but he made the point that the underbody condensor is cheap compared to the others so even if it's damaged it's not that big a deal.
12-27-2005, 10:54 AM
#5
Drifting
12-27-2005, 12:28 PM
#6
Three Wheelin'
Thread Starter
I investigated the Scotts condenser solution. They offer that part for around $450. I'm sure it's effective but decided a more factory approach was what I wanted and didn't want to drill any holes in my car. I also decided on a comprehensive approach...upgrade everything, not just replace one or two parts -- bring the whole system into the present.
Incidentally, Scotts also recommended sticking with or coverting back to R12. I am undecided on that, but currently leaning toward keeping my system R134.
Incidentally, Scotts also recommended sticking with or coverting back to R12. I am undecided on that, but currently leaning toward keeping my system R134.
12-27-2005, 12:42 PM
#7
Drifting
Originally Posted by Jastx
I investigated the Scotts condenser solution. They offer that part for around $450. I'm sure it's effective but decided a more factory approach was what I wanted and didn't want to drill any holes in my car. I also decided on a comprehensive approach...upgrade everything, not just replace one or two parts -- bring the whole system into the present.
Incidentally, Scotts also recommended sticking with or coverting back to R12. I am undecided on that, but currently leaning toward keeping my system R134.
Incidentally, Scotts also recommended sticking with or coverting back to R12. I am undecided on that, but currently leaning toward keeping my system R134.
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12-27-2005, 01:04 PM
#8
Three Wheelin'
Thread Starter
I wish there were a simple way to convert the mass of duct work behind the dash to allow fresh air through the center vent and air condition it, rather than the center vent just used for recirculated air.
12-28-2005, 02:23 PM
#9
Three Wheelin'
Join Date: Aug 2005
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I too will be performing an AC upgrade in the not too distant future. In Florida its a must have and mine's leaking somewhere I think. Next month I'm going to run it down ot an AC shop and have them evac, clean and refill the system and see if its just a leak that can be repaired or needs more serious efforts. If its the latter, I'll be interested in this new kit. Looks like really neat stuff. Thanks, in advance.
