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Posted by: McMark Jan 5 2015, 09:13 PM

We're doing an A/C install on a 3.2 project car and I though ya'll might like to see how it goes.

First I made a rough mockup of the location to test fit the setup in the car. This is just a TINY bit too high. I need to move it down and outwards a bit to clear things.




Once I had the general location I started making paper templates of the mount. It's a bit like putting together a puzzle, but instead of finding where pieces go, you just make your own as you go along. This will be made out of 1/8" plate most likely. The three circles you see will be bolts. The mount will be two pieces -- one underneath the tin and one on top. The tin will be sandwiched in between the two.





Oh man. How do I STILL not have a CNC plasma cutter.

Posted by: JmuRiz Jan 5 2015, 09:18 PM

Very neat, a higher power engine like a 3.2 or 3.6 would have no issues with a/c.
Didn't someone modify 3.2 heat exchangers on their /6 conversion? Good heat and a/c would be a dream on a 914/6!

Posted by: McMark Jan 5 2015, 09:19 PM

These are just typical 914-6 headers. This car may also be getting a gas heater system.

Posted by: shoguneagle Jan 5 2015, 09:56 PM

The 3.2 heat exchangers can be modified and used. The modification relates to having a straight shift bar from the firewall to the shift point on the transmission and putting a trough for clearance in the left heat exchanger.

I have modified my left exchanger to reflect these changes and they are working including the shifting. Not a big issue other than taking your time to set the clearances and making sure the shift rod works properly.

Posted by: Mark Henry Jan 5 2015, 09:58 PM

What would be real cool, or should I say hot, is if you could reverse the AC and turn it into a heatpump.

Posted by: ConeDodger Jan 5 2015, 10:28 PM

No no no! I do not want to see how it goes!

Posted by: GeorgeRud Jan 5 2015, 11:05 PM

Does anyone have a picture of the factory 911 heat exchangers used on a 914? I'm trying to imagine the routing of the exhaust and warm air, but can't quite wrap my head around this.

Posted by: JStroud Jan 5 2015, 11:08 PM

I'm with Rob.....if it goes well it could eventually cost me a lot of $$

Posted by: JStroud Jan 5 2015, 11:11 PM

Mark, with that hanging over to the side so far would this have to be installed after the engine was in the car? Seems like maybe the bracket too. Fun project.

Posted by: jeeperjohn56 Jan 5 2015, 11:30 PM

Mark, when you get this figured out give me a call and let me know what the cost will be. what kind of condenser are you using?would the stock one up front work? let me know when you get it worked out. John

Posted by: McMark Jan 6 2015, 02:08 PM

No, this will clear the engine shelf. I'm using the 914-6 tins as my guide. The compressor itself may have to be mounted after the engine is in, but that can be a good thing. If you have to pull the motor, it's nice to leave the AC lines unopened.


The condenser is an aftermarket unit. There really isn't anything fancy about a condenser. So we find one that works with whatever space restrictions we have. Also, making it as large as possible increases efficiency.

Posted by: GeorgeRud Jan 6 2015, 03:11 PM

I wonder if there is enough clearance to allow a condenser to be fitted under the engine lid (aka 911). If one would modify the lid to a 914-6GT double grill, it could allow a large condenser and allow a shorter hose run than a front trunk mounted one.

Please keep us informed.

Posted by: Cairo94507 Jan 6 2015, 04:52 PM

Just what I do not want to see.....the one aspect of my build on my car is that it does not have AC and here in the San Ramon Valley, it can get hot in the summer and early fall.

I am amazed with all of the hot roders out there installing custom AC units that fit into ashtrays, or so it appears, that we don't have a very compact and reliable unit to fit the 911 motored 914's - including the stock 3.2. I would love for my Six to have AC but that may bring the 914 Gods down on me.....

Posted by: Dave_Darling Jan 6 2015, 05:17 PM

Mark, I recall some concern about the mounting locations for other similar setups on 911 engines in the past. Specifically that the chain housing studs may not have been up to the stress and vibration of the compressor in the long run. Do you think that the extension of the mount that goes all the way to the motor mount will take enough of the load for that to not be an issue?

--DD

Posted by: Mueller Jan 6 2015, 05:27 PM

Nice mock-up Mark...if you need some billet parts CNC'd, let me know...I'll gladly do them for credit on that other motor!

Posted by: 76-914 Jan 6 2015, 05:40 PM

If that's a rotary compressor it won't vibrate nearly as much as the older units. Hey Mark, I'm watching this thread in hopes of receiving some enlightenment. I'd really like to learn the order in which the various components are installed, hose sizes, parts compatibilities, charging the system blah, blah. I hope to add AC within 18 months to Kugel which already has a compressor.

Posted by: crawler Jan 6 2015, 05:59 PM

If you guys ever get to Phoenix Arizona and need machine work. (Aerospace machine shop) give us a call. 480-926-2127

Posted by: Mueller Jan 6 2015, 06:18 PM

You don't use FedEX or the US Postal service

Nice little Mori lathe you've got!

Posted by: McMark Jan 6 2015, 09:30 PM

Yeah, I learned from those setups. This attaches to the motor mount, and that's it. The first three pictures in the thread are just a mockup mount. I needed to confirm the location would work without hitting the body. The real one (paper mockup) doesn't touch the chain housings, cam towers, etc. I won't know if it's rigid enough until I make it, but that's the next phase.

Posted by: Travis Neff Jan 7 2015, 09:12 AM

Posted by: jeeperjohn56 Jan 8 2015, 01:31 AM

Mark, if you need a car to work with let know,you can use mine for mock up.John

Posted by: McMark Jan 9 2015, 12:49 PM

Got the steel version done. It's very rigid and will work great. Just have to final weld the whole thing and make a few more sub-brackets.


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Posted by: GeorgeRud Jan 9 2015, 03:10 PM

Great looking! I think you may have finally come up with a workable solution for properly mounting an AC compressor on a 914-6. Have you checked whether the compressor location will allow you to swap out the oil filter on the oil tank with the AC compressor mounted? Worse comes to worse, it should be easy enough to move out of the way if needed for servicing, and should actually end up with better access to components than in a 911.

Posted by: Steve Jan 9 2015, 07:48 PM

Wow!!! Looks great, but will it interfere with factory heat exchangers? You could probably still use the right side and or a fan for the left side.

Posted by: McMark Jan 9 2015, 09:19 PM

I've realized there is too many combinations of components to offer a 'kit'. This will probably be full install only, with each setup custom tailored to the specific setup of each car.

Posted by: Steve Jan 10 2015, 10:30 AM

I understand, but it would be awesome if you offered a kit that just included the pulleys, bracket and hardware. We could easily source the rest for our particular application.

Posted by: Dave_Darling Jan 10 2015, 01:44 PM

I think he's saying that the bracket itself will probably have to be different for many of the installs. Maybe not unique to a particular car, but likely onesey-twosey...

--DD

Posted by: larryM Jan 10 2015, 09:02 PM

interesting idea

show me how this fits in a stock oem 914-6 engine mount with double sheave 3.2 lower pulley

- i don't see the pulley clearances on mine

i have all the oem 3.2 compressor mounts

Posted by: McMark Jan 11 2015, 10:47 AM

It doesn't fit on a stock 914-6 engine mount.
It doesn't fit on most of the currently available aftermarket engine mounts.

And so....

Posted by: McMark Jan 29 2015, 01:32 PM

Finally finished all these brackets. Figuring out how to handle the tensioning was the hardest part, but this works really well. The lower pivot of the compressor is a door-hinge style setup. Once that M10 bolt is tightened the tensioner will be doing very little work. I still have to trim the engine tin for belt clearance and the two holes for the mounting bolts.

All in all it's quite rigid and I've already test fit everything and it just clears. All in all this project took about 35 hours. And this definitely needs to be tailored to each individual setup. So a bolt on kit is impossible.


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Posted by: SirAndy Jan 29 2015, 01:50 PM

Posted by: ConeDodger Jan 29 2015, 07:38 PM

Saw it today in person! Installation looks factory...

Posted by: McMark Jan 31 2015, 12:17 AM

WHOA! Thanks to jcd914 (Jim) for pointing out that the 3.2 used just the crank pulley for A/C. The second groove on the fan pulley is not used. Time to order a new belt. WHEW!

Posted by: Steve Jan 31 2015, 10:53 AM

Too funny.. I was wondering why you had that dual fan pulley on there. I thought it was a clearance thing. My 3.2 came with AC and only had the crank dual pulley.

Posted by: Gary Feb 1 2015, 06:49 AM

Really slick!

I'm guessing the "handle bar" that's bolted to the top of the compressor is used set the tension?

Posted by: jeeperjohn56 Feb 1 2015, 02:04 PM

Mark, are you going to make more mounts for 3.2 motors? what will you charge for the whole set up and installation? let me know please. John

Posted by: mepstein Feb 1 2015, 02:12 PM

Wow! Nice job! Real heat exchangers become available for a 6 and now an a/c option. Really opens up the possibilities to having an all weather car.

I understand you set this needs to be tailored to each individual set up but does that hold true for a 3.2 install - meaning, can you make a kit for the 3.2's or is that still not possible?

Posted by: okieflyr Feb 1 2015, 06:27 PM

That looks sweet!
My question is do you think a center belt idler pulley would help with belt flutter given it's length? I can see the damper on the compressor but a belt damper may be beneficial as well?

Posted by: Cairo94507 Feb 2 2015, 06:20 PM

I just hate that McMark has figured this out! I would LOVE to add AC to my Six as it gets pretty darn hot where I live and it would be so cool (see what I did there....) to have AC blowing while cruising in the summer. But I will probably be condemned to burn in Hell if I try to put AC in my car in addition to the 3.2 engine.

Posted by: bcheney Nov 17 2016, 05:44 AM

Great work. Why not at least offer a bolt on kit for someone doing a 3.2 like this one?

Posted by: 914dave Nov 17 2016, 06:52 AM

This is exciting! I'm going to assume that use of the stock 3.2 a/c bracket for a rotary type compressor is too high in the engine bay. That's the route I was thinking of using. I like the fresh air box you came up with.

Posted by: gms Nov 17 2016, 08:52 PM

I would have never guessed you could fit that in with modifying the firewall
nice work