Classic Retrofit : Electric AC & Heat!

[Duc Hunter]

Originally Posted by chrisbalich

It matters not that you didn't start the thread; you chose to reply...and you're obviously subscribed. Once you open the door, it doesn't close behind you automatically.

We do not peruse the entire breadth of the internet looking for questions. But once we've fielded one, we follow-through until it's done or we ask them to reach out via another method.

The owner of the company I work for does answer questions online...or I do it. You'd be surprised how easy it is to get people to reach out via your preferred channels if you simply ask.

Best of luck in your ventures.

Sorry as one of their first customers I can’t let this all go by. I have had my CR A/C since early 2018! Thats over 6 years! Jonny and CR has been great on balance. They worked with me amazingly well during my setup and testing. When I had issues they helped me sort them out. I have also seen how they have worked with many of their customers and prospects over the years. Yes they are busy, yes sometimes they don't update every day or week, even if they are on here answering other threads, etc. SO WHAT! Jonny also owns his own car and aside from being a vendor is a valued member of the community. Maybe he is out here doing research on his own car, or any number of others things we all do here on Pelican. Is he perfect, no. Are any of us, certainly not. Has he been great, to me and many others, yes!

Demanding he be more responsive is one thing, and while I know he strives to be as responsive as possible, he would be the first to admit he wishes he could do more. There are just not enough hours in the day. Work, family, life all has to be balanced. Pointing out that you have seen his green dot while waiting with baited breath for his reply multiple times, and then attacking him here publicly for not being available all the time sounds more like one of my stalker ex-girlfriends, than a reasonable customer or prospect who understands the challenges of a business like his. Sorry, but true. If I were the owner of CR I would just not sell you a unit at this point, ever. Jonny though is more tolerant that I, or than you give he and CR credit for.

Interestingly Jonny and CR don’t need your passive aggressive “best wishes on your venture.” He and the CR HAVE a successful business, it’s growing and innovating, and thriving. We should be lucky and happy they still cater to folks like us while also supplying the likes of Singer, Guntherwerks, etc. Many vendors get to that level and forget the do-it-yourself folks, because even the nicest of us can be a PITA to deal with at times (I probably was).

Everyone needs to be nicer to each other out here, and usually this community is. Rant over. Beer time!

[Tom_in_NH]

I, for one, am very grateful for the innovations these small companies develope for our aging cars. CR has continued to provide products and technology that didn't exist before they arrived in the scene. From what I've observed in this forum, he's been as responsive as I could hope, given the fact that it's a one or two man operation.
I'll patiently wait for his latest iteration of the CR electric AC/heat system and integrate it into my 911 when Jonny says it's finished cooking.

[usera]

Originally Posted by chrisbalich

It matters not that you didn't start the thread; you chose to reply...and you're obviously subscribed. Once you open the door, it doesn't close behind you automatically.

We do not peruse the entire breadth of the internet looking for questions. But once we've fielded one, we follow-through until it's done or we ask them to reach out via another method.

The owner of the company I work for does answer questions online...or I do it. You'd be surprised how easy it is to get people to reach out via your preferred channels if you simply ask.

Best of luck in your ventures.

This is a bit heavy handed. I am not surprised that Johnny would choose to leave these threads. Every CR thread eventually has someone telling him that there is an inherent flaw in the design, that they can do it better or that another company makes colder AC units.

It is okay to be frustrated, it is another thing to scold someone publicly for not replying to a forum thread in a timely manner. Forums are not a main communication channel.

[almostordinary]

I started this thread, and I am just as excited as the day I saw the YT video and shared with the community here.

In due time, and when it's ready... I for one will be ready.

Thank you Jonny

[Duc Hunter]

Originally Posted by usera

This is a bit heavy handed. I am not surprised that Johnny would choose to leave these threads. Every CR thread eventually has someone telling him that there is an inherent flaw in the design, that they can do it better or that another company makes colder AC units.

And today I have not seen anyone build a better system than what CR offered. There are many good ones out there, they all have their merits (I have a nice non-CR setup in my 3.2), and I think CR's is the best.

My Gen 1 CR system was keeping me cool today. It's currently 91 in the shade here, humidity is a balmy 72%, and the feels like in the shade is about 107. Rough weather for any A/C, even the A/C in my 2021 Jeep Wrangler, let alone a 50 year old 911. Thank you Jonny & Co.

[spoke]

@Jonny H

My engine is being rebuilt and I want to get rid of the v-belt alternator drive. Clewett has a flat belt solution with stock speed ratio.

https://www.clewett.com/index.php?main_page=product_info&cPath=60&products_id=445

With this work with the high output alternator? I like it because it has a tensioner instead of shims to tighten the belt.

[Jonny H]

Originally Posted by spoke

@Jonny H

My engine is being rebuilt and I want to get rid of the v-belt alternator drive. Clewett has a flat belt solution with stock speed ratio.

https://www.clewett.com/index.php?main_page=product_info&cPath=60&products_id=445

With this work with the high output alternator? I like it because it has a tensioner instead of shims to tighten the belt.

Yes, it'll work. Ideally you want a ratio of x1.8 (or faster) from crank to alternator.

x 1.8 is the ratio on the SC and Carrera 3.2 with the standard V belt.

[SFR]

Looking for an update on the heat option (would need the retrofit version) - anyone know the status (@johhny H)?

[mikedsilva]

my engine is going to be rebuilt in the first half of 2026. My plan is to install the CR alternator and high gauge wiring at that time.

Is it safe to assume that when the upgraded kit (heat and cooling) comes out, the alternator will still be the same?

[Gonbad]

Originally Posted by mikedsilva

my engine is going to be rebuilt in the first half of 2026. My plan is to install the CR alternator and high gauge wiring at that time.

Is it safe to assume that when the upgraded kit (heat and cooling) comes out, the alternator will still be the same?

I think that is safe. WOSP alternator is a robust unit and powerful for its size. It's the size that is the limiting factor and I don't believe there is a more powerful unit that will fit within the unique confines of a pre 964/993 fan assembly.

I am not familiar with the 964/993 alternators and I am don't know the specifications of their fans. Is it possible to retrofit the M64 engines shroud and fan to an earlier motor?

I have seen custom brackets and pully assemblies utilizing larger alternators on race prepped 911's but those have also been using a flat fan configuration.

[Jonny H]

Originally Posted by Gonbad

I think that is safe. WOSP alternator is a robust unit and powerful for its size. It's the size that is the limiting factor and I don't believe there is a more powerful unit that will fit within the unique confines of a pre 964/993 fan assembly.

I am not familiar with the 964/993 alternators and I am don't know the specifications of their fans. Is it possible to retrofit the M64 engines shroud and fan to an earlier motor?

I have seen custom brackets and pully assemblies utilizing larger alternators on race prepped 911's but those have also been using a flat fan configuration.

The heat pump (heating and cooling) will still use the 175A Wosp unit - same as per our AC systems. The heat/ac system will come with a factory default current cap set to 75A so there is plenty of headroom left for other electrical items in the car.

The internals for the 240A 964/993 alternator are physically too large to fit in the 911 housing. TBH, our systems work fine with the 175A and the 240A is only recommended if you have an exceptional electrical requirements. It also requires changing to a polyrib belt.

I'll check in with a general update on heat pump system in a couple of days.

[LukasM]

Originally Posted by Jonny H

I'll check in with a general update on heat pump system in a couple of days.

Very much looking forward to the update Jonny! Like a lot of folks on here I would be interested what the new system weighs in total, ideally compared to all the parts you are taking off (heater blower, ducting, headers vs. heat exchangers, controls and cables etc).

Cheers,
Lukas

[PeteKz]

If it works as advertised, I don't care what it weighs!

[lateapex911]

Wellll, this IS interesting. good thing my project has taken so long. Ha.

Looking forward to an update,

[Gonbad]

Originally Posted by Jonny H

The heat pump (heating and cooling) will still use the 175A Wosp unit - same as per our AC systems. The heat/ac system will come with a factory default current cap set to 75A so there is plenty of headroom left for other electrical items in the car.

The internals for the 240A 964/993 alternator are physically too large to fit in the 911 housing. TBH, our systems work fine with the 175A and the 240A is only recommended if you have an exceptional electrical requirements. It also requires changing to a polyrib belt.

I'll check in with a general update on heat pump system in a couple of days.

Thanks for the reply and I appreciate the work you’ve all put into this effort. I will be in the market for this soon as I am deleting what’s left of the HVAC in my car.

[lateapex911]

So I’m trying to dig up info on the new ac/heat system. I have a 73 911E LHD. With the RS plastic tank.
I’ve read the CR forum instruction and have a rough idea of the layout, components and needed changes.
So far:
- new alternator. And new wiring in a couple places. Engine is current out and I just finished some harness upgrades so now is the time for that.
- cut off drivers side batt box and cap, OR create attachment structure/fastening points and shields in drivers quarter for fan and hoses and heat excngr.
- figure out interior ducting and outlets. Dash is non AC. Acckk.

I’m currently planning on new carpets and doorcards and while I’m there it’s time to redo the audio. The existing set up has Alpine and Nakamichi amps in the smugglers box. The Nak amp stays, a classic a/d/s amp will replace 2 Alpines.


With the CR compressor going in the smugglers box all the audio gear needs a new home.

So… the big question is: what changes in terms of physical space needed will the addition of heat require? I assume that in a heat pump system such as this, that making heat is essentially reversing the normal flow of the core components so I’d anticipate changes to the components but no large item additions? Perhaps a reversing valve but there’s space in the smugglers box it seems.

Does anyone have any intel?

Other considerations: what have people done with the interior controls? It would be cool if it looks vintage.
Also. My dash is pretty new. In good condition. How to handle AC venting?I have decent fab skills.

[SpyderMike]

Here is one idea...I used aluminum aircraft vents. It was easy to route the hoses to them.



You could change the metal plate to something more "vintage" (and the switches too).

[LukasM]

Originally Posted by lateapex911

So I’m trying to dig up info on the new ac/heat system. I have a 73 911E LHD. With the RS plastic tank.
I’ve read the CR forum instruction and have a rough idea of the layout, components and needed changes.
So far:
- new alternator. And new wiring in a couple places. Engine is current out and I just finished some harness upgrades so now is the time for that.
- cut off drivers side batt box and cap, OR create attachment structure/fastening points and shields in drivers quarter for fan and hoses and heat excngr.
- figure out interior ducting and outlets. Dash is non AC. Acckk.

I’m currently planning on new carpets and doorcards and while I’m there it’s time to redo the audio. The existing set up has Alpine and Nakamichi amps in the smugglers box. The Nak amp stays, a classic a/d/s amp will replace 2 Alpines.


With the CR compressor going in the smugglers box all the audio gear needs a new home.

So… the big question is: what changes in terms of physical space needed will the addition of heat require? I assume that in a heat pump system such as this, that making heat is essentially reversing the normal flow of the core components so I’d anticipate changes to the components but no large item additions? Perhaps a reversing valve but there’s space in the smugglers box it seems.

Does anyone have any intel?

Other considerations: what have people done with the interior controls? It would be cool if it looks vintage.
Also. My dash is pretty new. In good condition. How to handle AC venting?I have decent fab skills.

The new version with heat apparently no longer places the compressor in the smugglers box, it goes where the battery sits in the impact bumper cars. The battery then gets replaced by a much smaller Odyssey battery, thats sits right behind it. The CR website and blog has pics of the test mule running this system.

I assume this change was made to streamline CR's production and inventory, as RHD cars don't have a proper smugglers box and they had to offer 2 systems in the past.

As for condensor placement - left front is the cleanest in terms of routing hoses and for weight distribution. If your 911E is not that original anyway, or you don't foresee ever selling it, I'd cut it off and weld in the 911 ST covers from Restoration Design, ideally both sides so you can install a Carrera cooler with fan (slippery slope with your money... ) Otherwise, left rear is also ok, you will need to drill some holes and make some brackets.

As for the vents - easiest solution is to fit a F150 ball vent instead of the clock, together with the rotating underdash vents from CR. Although I have to say the aircraft vents from SpyderMike also look great.

The old system just required a single push button to turn it on or off, temp was preset by the factory (you can change it in the firmware). The rest was controlled by the existing control panel. The new system removes all this, along with the cables, blend valves etc, and switches to an electrical control panel with servo controlled blend valves.

Have a read here:
https://www.classicretrofit.com/blogs/news/2025-is-the-year-of-the-heat-pump-for-porsche-911s

Originally Posted by SpyderMike

Here is one idea...I used aluminum aircraft vents. It was easy to route the hoses to them.



You could change the metal plate to something more "vintage" (and the switches too).

Nice install Mike!

[lateapex911]

Originally Posted by LukasM

The new version with heat apparently no longer places the compressor in the smugglers box, it goes where the battery sits in the impact bumper cars. The battery then gets replaced by a much smaller Odyssey battery, thats sits right behind it. The CR website and blog has pics of the test mule running this system.

I assume this change was made to streamline CR's production and inventory, as RHD cars don't have a proper smugglers box and they had to offer 2 systems in the past.

As for condensor placement - left front is the cleanest in terms of routing hoses and for weight distribution. If your 911E is not that original anyway, or you don't foresee ever selling it, I'd cut it off and weld in the 911 ST covers from Restoration Design, ideally both sides so you can install a Carrera cooler with fan (slippery slope with your money... ) Otherwise, left rear is also ok, you will need to drill some holes and make some brackets.

As for the vents - easiest solution is to fit a F150 ball vent instead of the clock, together with the rotating underdash vents from CR. Although I have to say the aircraft vents from SpyderMike also look great.

The old system just required a single push button to turn it on or off, temp was preset by the factory (you can change it in the firmware). The rest was controlled by the existing control panel. The new system removes all this, along with the cables, blend valves etc, and switches to an electrical control panel with servo controlled blend valves.

Have a read here:
https://www.classicretrofit.com/blogs/news/2025-is-the-year-of-the-heat-pump-for-porsche-911s



Nice install Mike!

Super helpful. My memory has in it a picture of a compressor in the battery position, but I couldn't remember where I saw it, maybe in this not so short thread? I missed the blog on the website, so thanks for the tip there..

That placement is a problem as I have the plastic RS tank. I do like the tank, because it's unique and cool, but, TBH it's pretty much "Well used"...the car was driven into and out of NYC to NJ when I got it from the previous owner. It was a euro import/gray market car back in 73 or so, I'm guessing the tank might have been part of that?

Anyway, it's got some NYC scratches and gouges.

The good side of the placement is that it leaves the smugglers box open for the audio gear. But now I'd need a new tank, and /or restoration of one.

I don't mind cutting the battery box, it was badly rusted back in 93 when I did some repairs, I can always just make a new one down the road if I get all "original" about the car. But that ship has sailed and while it hasn't sailed off the edge of the ocean, it's pretty far out there lol. For sure that location is far better.

Good point about a cooler, you know me well, ha. I need to add a proper oil cooler. (Another slippery slope. $$$, and a new front bumper?, Elephant lines? Through rocker lines? )

I already run a LiFePo battery, but it's in the passenger box, well, kinda, much of the box remains empty.

Then there's pricing, I figured the kit would be $3-5K. hahahaha, dumbass. $5900 IIRC.
And, a new alternator ($1200.)
Does anyone know what the tariffs and duties and such actually run?? I tried researching DHL, but they must be under the requirement to not use the term "Tariffs" ha. Seemed like it would be about $700-ish for the kit to get it on my doorstep.

And, of course, the heat /AC unit will be adding an non trivial price bump.
Once installed there's the charging of it, another fee, this is looking to be easily into 5 figures even with me doing the work.

Alternator $1200, and kit, $5900, plus shipping etc of ??/ so...$8K? Then Dash mods and parts for $300 or so, And the tank purchase (maybe sell the plastic RS tank), so, sorta not too bad, but pipes etc for $400, then the Freon fill for I dunno, $500, has me at $9200. Plus the new system heat and better distribution and control, well, that's gotta add a couple , so, $11K+???

How does that sound to those who have done it?

[SpyderMike]

My CR hybrid system...it includes a cost sheet on post #165.

https://forums.pelicanparts.com/porsche-911-technical-forum/1144750-1985-ac-project.html