To A/C or not to A/C??

bluecoupe30!

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Well, you reside in California. Temps may be more extreme than up here in BC. My Coupe does not have a/c either. When I first started driving my Coupe, I believed that was the thing to add. Then I learned of all the things that can contribute to cabin heat. Absence of drain tubes, deteriorated heater box seals, all that window glass, untinted, missing muffler heat shield, heater bypass option. Lots of things can contribute to excess heat inside our cars. Back in the '60s, '70s, exhaust insulation was just not ever considered. You may source all of the pieces required to add original 1970's German a/c onto your car, but there is a chance you may not be satisfied with the performance unless you address these other weaknesses. Just my opinion however. Others may have something that will suit your circumstances. Best of luck, and let us know how you solve this one. Mike
 

adammusavvir

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Well, you reside in California. Temps may be more extreme than up here in BC. My Coupe does not have a/c either. When I first started driving my Coupe, I believed that was the thing to add. Then I learned of all the things that can contribute to cabin heat. Absence of drain tubes, deteriorated heater box seals, all that window glass, untinted, missing muffler heat shield, heater bypass option. Lots of things can contribute to excess heat inside our cars. Back in the '60s, '70s, exhaust insulation was just not ever considered. You may source all of the pieces required to add original 1970's German a/c onto your car, but there is a chance you may not be satisfied with the performance unless you address these other weaknesses. Just my opinion however. Others may have something that will suit your circumstances. Best of luck, and let us know how you solve this one. Mike
That is an excellent advice. Thank you. I think that would be a way to go and address it first before installing a/c . I never thought what would contribute to cabin heat like that.
 

thehackmechanic

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Look for my posts here on the site, and read my book, "Just Needs a Recharge: The Hack Mechanic Guide to Vintage Air Conditioning." I retrofitted a/c into my E9 20 years ago. There are a few things that makes it harder on an E9 than on, say, a 2002:

--If you want it to look stock, you need a console and faceplate from an original car (yes, Markos is 3D-printing the faceplates).

--You need the "intermediate piece" that sits between the evaporator assembly and the ductwork.

--You need the copper pipes that go through the firewall and right-angle-bend behind the glovebox. It's not like a 2002 where you can just run rubber hoses through. There's very little room back there. The early E12-based E24 also uses this kind of right-angle plumbing. Don't know if they're compatible, though. Certainly anyone who does copper work could bend one up, but I've never sourced it out.

The evaporator assembly is the same as a Bavaria, and the intermediate piece is similar enough to use.

If you can't find a rotted car that has these things (more difficult than it used to be), it's tough to put together a package that'll look correct in the interior. In the 2002 world, people do a variety of things, including using modern climate control boxes (heater core and evap core in the same box) and a console that's not original, but the more valuable E9s get, the more that approach is dicey. I drove mine for easily a decade with the original non-a/c console around the evaporator assembly, and no faceplate, as I couldn't find an a/c console and faceplate, at least not one I could afford.

The under-hood stuff (rotary-style compressor, big modern parallel flow condenser and fan) is all easy and like any other car.

--Rob Siegel

 

Willem Tell

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You can also install a heater bypass valve to avoid hot heat in the cabin
I agree. You might try this easy mod for a season before deep-diving into the AC mods.
Rob Siegel also did a great write-up on the bypass mod. I followed his direction, and it makes a world of difference in the summer!
A couple of angled hoses, clamps and the bypass valve... done in an after noon (not counting getting the wires into the cabin ;) )
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Buildit

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I will have to disagree with a few of the posts noting poor cooling effectiveness, chunkiness, etc.

I installed a Sanden pump (which has virtually no draw on the engine load—AND I HAD AN AUTOMATIC!!), new lines, new evaporator, and switched to R-134a.

Albeit there are only 2 vents that blow air, they are quite cold and more than sufficient for the driver and passenger. Trust me when you are baking you will appreciate the air!

I still feel that this is a necessary upgrade and well worth the money spent in the long run.
Yes Sanding 508 style compressor needs only fraction of resistance vs. old York reciprocating compressors.
 

Buildit

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We have worked out I think all most all the issues with installing a modern AC and heat evaporator in coupes. Drain location, cable operation, fitment in car, path for new AC evap lines or use old path if orig AC car,

We created new systems for classic E10's and E21's installed 100's of them, retrorfitted many hundred old systems. We modified this unit in size and with left hand ac line fit for coupe.

Our installs on coupes and customers who purchased kits in Europe and US seem to have been 100% successful but have only fitted 10 or so.

Only challenge for some is removing their old clunky heater (BMWfiles have an affinity for originality that most other classic car folks do not want the dated heat and ari systems as just trouble). So BMW owners are catching up in their thinking.

This system comes with good instructions (not perfect we continue to refine). Complete kit but we do not have reproduction compressor mounts yet (working on it) Have original to copy and adapter plates for Sandin 508

Our experience with way glass raps over head in cockpit of E9 AC is really a must any any summer driving ?

This is real solution to modernize your car ! Is developed from modern off the shelf components you can service easily and very inexpensively if ever needed vs. trying to use an old EVAP box from say a 80's or 90's E28. We anticipate in all the coupes there will be some variances we can help with. We also have original AC front plate we are going to reproduce for non AC cars. Note: don't need to install but completes the look. Old original plates out there available also

https://www.dtechparts.com/e9-cs-coupe-air-conditioning-heat-kit-inside-evaportor-controls-complete/

Contact us direct for more info ? Access to instructions, example install pics, Q&A

This underhood kit is all you need under the hood less the compressor bracket which we have in design to manufacturer. Probably have it done before you need

Stay "cool"
 

halboyles

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I'd tint the windows first.
Besides keeping the internal temps down, tinting also blocks IR and UV rays protecting your very expensive leather and plastic interior. 3M makes great ceramic products, some of which are almost transparent. We also use a front windshield shade designed for the e24. It fits almost perfectly with just a little trimming of the upper part. This alone lowers the temp considerably. Cheap first steps to a cooler coupe!
 
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