Printable Version of Topic

Click here to view this topic in its original format

914World.com _ 914World Garage _ Under cowl A/C unit design input thread and gauging interest

Posted by: Chris914n6 Jul 23 2014, 08:24 PM

Dusted off another one of my projects from when I first built my waterpumper. Heater and A/C replacing the factory fresh air blower unit.

History. I built the unit using a tube/fin core from my Uncle's buddy Dave @ Hotrod Air. HRA went under in the recession and so did the company that actually made the cores. Oddly enough this is a benefit despite having made some really nice wood vacuum forming bucks.

The good news. For version 2 I went with separate heater and evap cores. The heater is off the shelf, I just need to trim the tubes. The evap I'm having made by a company I met at the 2013 SEMA show and is modern plate type. Blower is a 3 speed.

The nitty gritty. Uses stock controls and stock air deflector boxes. Hoses run Pass side like DPD/VPC. I did design a setup for modern controls and deflector boxes with a separate side vent path, but it's a bit complicated to make.

I have plans to offer 3 versions.

Model B - A/C and heat for us waterpumpers. Runs recirc through the heater tube holes so no cutting. Unit is too tight of a fit for fresh air. I'll have an optional drainage piece for those that don't seal the grill.

Model A - A/C only for aircooled cars. Because the heater tube holes are being used for heat, air intake will be from the grill opening. You could cut a 2.5" hole in the cowl for recirc instead if you wanted or use just one heat exchanger.

Model H - Heater only for waterpumpers. Same unit as the A/C only except that recirc is possible through the heater hose holes OR model B with no evap, haven't decided yet.

In the kit - Main unit, mounting brackets, air hoses & clamps, blower wiring, expansion valve, instructions.

Options - Cabin filter. Grill water drain.

The other pieces...
Condensers- it depends on the radiator you using and what you can make fit, no point in me trying to keep an inventory. The exception could be a replacement to the DPD/VPC Condenser unit for air-cooled cars, I haven't gotten past doodles yet.
Receiver-driers of the universal type can be had on Ebay for under $15 shipped, I'll pick one out for you, same with the pressure switch.
Hoses, too many variations and too much overhead for me, but Vegas has 3 places that will build them on your car so I assume that's practically everywhere. Prices trend $100-$150.
Hard lines- Research has spec'd it as 6063 aluminum. DPD/VPC used hard lines along the rocker and up the wheel wells.
Heater hose- nothing special about it but it's long and 5/8"ID.

Prices... about the same as the Hotrod kits. Manufacturing time is unknown and the biggest factor of course.

I will have to buy 50+ evap cores to make this happen, so even if you are a year or more away from buying one speak up.

Any feedback and who wants one?

Posted by: rnellums Jul 23 2014, 10:24 PM

In for H

Posted by: Chris914n6 Jul 23 2014, 11:03 PM

I promised a pic in another thread. Problem is I can't show the unit without giving away the details on how I got it to fit to the 2 other known fellas trying to do this. So this will have to do. It's all V1 stuff with the buck and pieces for the flapper boxes I was going to run with.

IPB Image

Posted by: 914dave Jul 24 2014, 04:38 AM

I'd be interested in an AC only unit for my six conversion. Will the the AC will function in the standard heat and defrost channels? I would really like to hide the unit under the dash instead of below. I have a front mounted cooler that I made that should allow for the condensor, if its not too big. I have a 14 1/2 x 7 x 4 1/2" envelope to mount the condensor in direct air flow. There's a fan behind the oil cooler for traffic situations.
Attached Image
Attached Image

Posted by: DBCooper Jul 24 2014, 06:58 AM

Model B for me. I'm so happy you're taking this on, one of the few times I can remember that procrastination's worked out for me.

Posted by: Philip W. Jul 24 2014, 07:27 AM

Model A --

so do i understand correctly that this would be put in place of where the current fresh air box is, under the cowel, just in front of the gas tank?

can you give me more information about how this all would hook up, such as the other necessary parts and how it hooks up, wiring, evap, compressor etc.

Posted by: pdlightning Jul 24 2014, 12:33 PM

QUOTE(Philip W. @ Jul 24 2014, 06:27 AM) *

Model A --

so do i understand correctly that this would be put in place of where the current fresh air box is, under the cowel, just in front of the gas tank?

can you give me more information about how this all would hook up, such as the other necessary parts and how it hooks up, wiring, evap, compressor etc.

I am definitely in for Model B . I have a LS conversion and have been looking for someone like you! smile.gif

Posted by: 76-914 Jul 24 2014, 01:32 PM

+1 on a B, here.

Posted by: Chris914n6 Jul 24 2014, 01:43 PM

QUOTE(914dave @ Jul 24 2014, 03:38 AM) *

I'd be interested in an AC only unit for my six conversion. Will the the AC will function in the standard heat and defrost channels? I would really like to hide the unit under the dash instead of below. I have a front mounted cooler that I made that should allow for the condensor, if its not too big. I have a 14 1/2 x 7 x 4 1/2" envelope to mount the condensor in direct air flow. There's a fan behind the oil cooler for traffic situations.


It is a direct replacement in form and function for the stock fresh air box. 2 outlets to the stock air deflector boxes. For aircooled motors the heat side stays stock.

In the first pic I have a piece of cardboard blocking the defrost channel from fresh air to get more out of the side vent. Foggy windows not much of a problem where I'm at.

The smallest aftermarket parallel flow condensers I've seen were 10"x18" or 12"x16". Might be something shorter in OEM. Found an 84-89 911 130mm x 477mm for ~$500 barf.gif It's essentially just a high pressure ready heat exchanger so something else could work.

Posted by: Chris914n6 Jul 24 2014, 02:14 PM

QUOTE(Philip W. @ Jul 24 2014, 06:27 AM) *

Model A --

so do i understand correctly that this would be put in place of where the current fresh air box is, under the cowel, just in front of the gas tank?

can you give me more information about how this all would hook up, such as the other necessary parts and how it hooks up, wiring, evap, compressor etc.


You will need a compressor on the motor, pretty sure there is a kit of sorts by a member. You will need ac hoses made (local shop ideally) to go from the compressor to the receiver-drier and condenser (usually mounted in the front truck), from the condenser to the expansion valve and evaporator (my contributions), then from the evaporator back to the compressor. I think it was Bowlsby that had the VPC/DPD system install manuals on his website, the way they did it can't be beat.
You will need an A/C on/off switch (I've got a few ideas to share). The new blower is a 3 speed like the stock controls so that's easy to wire, I might make a harness.

Posted by: andys Jul 24 2014, 02:49 PM

QUOTE(Chris914n6 @ Jul 24 2014, 12:43 PM) *


The smallest aftermarket parallel flow condensers I've seen were 10"x18" or 12"x16". Might be something shorter in OEM. Found an 84-89 911 130mm x 477mm for ~$500 barf.gif It's essentially just a high pressure ready heat exchanger so something else could work.


When I was kicking around some ideas and trying to find a small evaporator, I considered a power steering oil cooler as they're available in small sizes. Attach an expansion valve and fittings.

Andys

Posted by: Chris914n6 Jul 25 2014, 01:52 PM

Ok, a teaser pic...

IPB Image

Looks like I'll need to add a rubber wiper mount to my 914rubber shopping list.

Posted by: Chris H. Jul 25 2014, 02:04 PM

Model B for me.

Posted by: timothy_nd28 Jul 25 2014, 02:52 PM

Thanks for taking on this project. beerchug.gif I had a plan of redesigning the fresh air box by use of a 3d printer, but my project never gained traction. What type of metering device did you have in mind?

Posted by: Chris914n6 Jul 25 2014, 07:11 PM

Thanks for the Thanks. I live in Vegas, it was kinda mandatory happy11.gif

V2 is turning out better in every way over V1... guess sitting on it for 10 years wasn't such a bad thing yellowsleep[1].gif

Metering device?

Posted by: racerx9146 Jul 25 2014, 07:35 PM

As for me, been thinking of this for some time. As I get older comfort trumps ultimate performance!

Hope this comes to reality.

Daron

Posted by: dadaDaveed Jul 25 2014, 09:39 PM

Ooh, Model B for me! Texas only has two seasons. Summer and Summerer.

Posted by: 7TPorsh Jul 25 2014, 10:05 PM

Ya, type B....SoCal like Texas.... biggrin.gif

Posted by: Chris914n6 Aug 8 2014, 06:51 PM

smash.gif smash.gif smash.gif smash.gif smash.gif smash.gif smash.gif

So 19 evaps spoken for on just World in 2 weeks felt like a good start. I've been building a full mockup of B that I'm hoping to get installed and release pics this weekend. I've got the design down to 1 body mod and a few screw holes, plus various ac hose holes in line with the DPD system.

Enjoy your weekend... I'll be smash.gif smash.gif smile.gif

Posted by: JmuRiz Aug 8 2014, 08:30 PM

A would be great, if only I could find some good heat exchangers for a /6 that work and don't cost a fortune. Maybe put the condenser in front of the oil cooler in the front.
Heat and a/c in a 914 would be awesome.

Posted by: dadaDaveed Oct 6 2014, 09:35 PM

How's it coming along?

Posted by: Cairo94507 Oct 7 2014, 06:44 AM

Wow AC in a Six would be perfect if it can be done and look right.

Posted by: timothy_nd28 Oct 7 2014, 08:27 AM

I'm in model B

Posted by: Philip W. Oct 7 2014, 08:51 AM

if this is happening for sure(it will be my winter project, prepping for next summers' heat) then i need to start accumulating all necessary parts, including the front pully, belt and bracket to hold the compressor, oh and the new light weight compressor. -
can anyone please post the contact information for the member that had made the new brackets and pully conversion etc? and the model of compressor-new light weight, low hp one?

thanks,

Phil

Posted by: dlee6204 Oct 7 2014, 10:15 AM

QUOTE(Philip W. @ Oct 7 2014, 10:51 AM) *

if this is happening for sure(it will be my winter project, prepping for next summers' heat) then i need to start accumulating all necessary parts, including the front pully, belt and bracket to hold the compressor, oh and the new light weight compressor. -
can anyone please post the contact information for the member that had made the new brackets and pully conversion etc? and the model of compressor-new light weight, low hp one?

thanks,

Phil


You talking about me?
shades.gif

http://www.914world.com/bbs2/index.php?showtopic=192917&hl=

Posted by: Philip W. Oct 7 2014, 01:17 PM

QUOTE(dlee6204 @ Oct 7 2014, 12:15 PM) *

QUOTE(Philip W. @ Oct 7 2014, 10:51 AM) *

if this is happening for sure(it will be my winter project, prepping for next summers' heat) then i need to start accumulating all necessary parts, including the front pully, belt and bracket to hold the compressor, oh and the new light weight compressor. -
can anyone please post the contact information for the member that had made the new brackets and pully conversion etc? and the model of compressor-new light weight, low hp one?

thanks,

Phil


You talking about me?
shades.gif

http://www.914world.com/bbs2/index.php?showtopic=192917&hl=

Yep!

Posted by: Chris914n6 Oct 9 2014, 02:31 PM

It's moving at the speed of life....

I should know better than to make plans for a full moon weekend. slap.gif
Then it was 120F in the "workshop" most days this summer. happy11.gif

But I did get a nice cardboard mockup built and fitted which helped finalize the design, before all the little mods took their toll, so the pic I wanted to show off with the hoses and stuff attached didn't happen as the box just wasn't solid enough. It just made more sense time wise to move on to the production unit.

So that's where it's at. I've spent the past several weeks going back and forth with the manufacturer (in China of course) about getting an Evap to do testing with. They say it's going to take 2 months if I order 1 or 50 so I should buy 50 lol. Other thing is I don't have a running car (planned for this winter) or upcoming hot weather to test with before the hot weather.

Jist of the B and H designs are AC and heater hoses run inside the pass heater duct/long. Air inlet from drivers heater tube hole with a provision for a 5"x5" air filter (cut up home filter). Comp to Condenser hose outside the pass long as it's generally a better route to the trunk condenser. Heater valve attached to the pass stock control box and uses stock heater lever cable.

Model A also has the hoses attach on the pass side like the under dash stuff so with the possible need of a hose extension or 2 it will play nicely.

In case you're wondering, this is a half cut pointing nose up.

IPB Image

IPB Image

Posted by: aircooledboy Nov 10 2014, 09:12 AM

I'm in for a Model B.

I've spent a lot of hours looking at the under dash unit I have, trying to figure out how I could just disassemble it and stuff the various pieces and parts in the empty spaces under the cowl. . . . idea.gif sawzall-smiley.gif

Since I have as much free time as the average man holding back the ocean with a broken broom, prol'y easier to buy one somebody else sorted out. beerchug.gif

Obviously if it is possible to buy the parts you have fabbed to make her fit, while using as many of the parts I already have s possible, that would be just sthuper. mrs.K.gif cheer.gif

Posted by: 914forme Jan 16 2015, 02:23 PM

Updates? Unit B for me please! beer.gif

Posted by: Chris914n6 Mar 29 2015, 03:05 PM

Almost done building my vacuum forming machine piratenanner.gif

Had to part with the off-the-shelf heater core as it limited the evap size too much, so now it's also made to spec. I've settled on an evap slightly larger than those on a Miata and Mazda3. It's also 30% larger than the dpd underdash unit.

That one (so far) heater only request will get the off-the-shelf unit laying on the bench and I'll just make a box to fit.

Couldn't get just 1 core for testing so I decided to finish V1 and install it in the car, to confirm calculations and essentially as a proof of concept. It will be a WCR15 and there will be pictures allowed w00t.gif

Timeline is now a show and tell at WCR15, about a month for the GB to get an real demand figure and some funding, 2 months to get cores delivered, then it's just assembly and out the door.

Posted by: Philip W. Mar 29 2015, 03:16 PM

cheer.gif beerchug.gif

Posted by: wes Mar 29 2015, 04:56 PM

piratenanner.gif

Posted by: Chris914n6 Mar 31 2015, 06:44 PM

Damn. Got a couple quotes to have the a/c hoses made today. $275 and $350.

If I buy the tool set, and parts online, $250.

I'm kinda obligated to invest in the tool set now. And I can use the 20 ton press for more than wheel bearings biggrin.gif

Posted by: quadracerx Mar 31 2015, 08:13 PM

Ill be in... Once you have inventory and are able to ship... Water pumper version... Heat and AC Please...

Posted by: 76-914 Mar 31 2015, 08:21 PM

popcorn[1].gif

Posted by: Chris914n6 Apr 4 2015, 08:34 PM

Hella fog light switch question. Are the new 'generic' ones the same as the originals as so the lighted knob and odd nut work?

Also, I have seen but can't find again, an insert, I recall from the vw bus, that is blue and had an air related symbol in white. If not then someone want to make a blue insert with a snowflake?

I think this is what I saw but in blue so it would light up.
IPB Image

Stock fog switch that I think would be ideal as the a/c switch.
IPB Image

Or if you're not picky the generic knob probably fits. Fairly sure this one doesn't light up.
IPB Image

Other options???

Posted by: Mike Bellis Apr 4 2015, 08:48 PM

Hurry up!

I want to place my order. biggrin.gif

Posted by: db9146 Apr 4 2015, 08:54 PM

I'm in for an "A" for an air cooled model.

Posted by: jim_hoyland Apr 4 2015, 09:01 PM

smile.gif nice work smile.gif Are you going to show us the prototype at WCR ? That would be way cool.....

Posted by: kid914 Apr 4 2015, 09:10 PM

interested in # 2 ( air cooled) beerchug.gif

Posted by: Gary Jun 25 2015, 05:02 AM

How's it going? I'm interested in a model A (aircooled) and soon.

Posted by: timothy_nd28 Aug 9 2015, 12:06 AM

Did this project stall out confused24.gif

Posted by: Chris914n6 Aug 9 2015, 11:37 PM

Stalled yes, but not out.

Been a series of unfortunate events. Electrical went to gremlin paradise during the time the car's been stored, missed my WCC deadline and my window. Then June was hot as hell and I couldn't stay outside for any significant time. My WD Black HDD has failed twice since May, lost the design files and the suppliers list. Luckily I still sketch/draft some things on paper but it's been like starting from scratch. Add to it I'm a pretty busy fellow without "challenges".

Posted by: euro911 Aug 10 2015, 04:39 AM

I'm interested in Model A, Chris.

WD HDDs should be renamed WMD ... I use 'Time Machine' and a portable back-up drive shades.gif

Posted by: boxsterfan Aug 10 2015, 09:12 PM

Would love to learn more about what you are doing? I'm trying to figure out how to get a better A/C system without cutting holes in the front trunk. Just my preference....

http://www.914world.com/bbs2/index.php?showtopic=261281&hl=


However, the big part is getting a combination heater/ac(evap) blower box. I see in the beginning of this thread, it appears you got something from Hotrod air (or similar)? Obviously, that thing has a controller. Looks like you were trying to customize it so that the knobs looked a little more correct in the 914.

Does the blower unit fit under the cowl (and slot for fresh air)? Are you able to get water drained away from it if it is hooked there?

Posted by: Chris914n6 Aug 11 2015, 01:10 AM

boxsterfan- I'm actually making a box that fits. Uses the 914 air directors/dash levers. All the "Hotrod" boxes are built for big Hotrod dashes. Plus I can build them with latest design cores, which are smaller, and keep the price in the same range.

The knob stuff is just the on/off switch for the compressor. I'm trying to find something that looks factory, like an insert in a repurposed fog light switch.

Drainage, for both rain washing and condensation, are accounted for.

Posted by: timothy_nd28 Aug 11 2015, 10:57 AM

Happy to hear that you haven't waived the little white flag! Entertain the thought of just selling your custom airbox with evap coil and blower (as a package option). For my conversion, I was planning on doing my own wiring, as the ECM controls the request for AC. I'm not sure how comprehensive your final kit will be, but for my LS conversion, I already have a compressor and condenser. I'm sure other water pumper conversions have provisions of their own as well.

Posted by: euro911 Aug 11 2015, 06:27 PM

Should I keep my old condenser handy? ('70's era dealer/vendor installed option) then source a new compressor & dryer for 134A?

Posted by: Chris914n6 Aug 11 2015, 09:03 PM

timothy_nd28- I'm only selling the unit and the few things needed to essentially replace an under dash unit. Too many engines with too many options to do a full kit, with too few buyers.

I am, as part of looking at the big picture, looking into solutions to the other pieces involved, like the switch and condenser, so 40 buyers don't need to blow time looking for answers to common questions. I will likely make an AC appropriate insert for the fog light switch as it's the best match for the interior, unless I find one.

euro911- At least until someone provides a new tech replacement. May or may not be me. Someone here made a kit for the Sanden for the T4.

Posted by: timothy_nd28 Aug 11 2015, 09:23 PM

I totally agree with you. Back to my original question on page one, what style metering device are you planning on using with the evaporator coil? If you are using a fixed orifice, then there will be no issue. However, if you are using a thermostatic TXV/Hblock dealy, will it be compatible with R-12 or are they rated for R-134 only?
I have a jug of R-12 buried in my back yard, and I wanted to put it to full use.

Posted by: timothy_nd28 May 8 2016, 07:26 PM

Any progress with the under cowl box? popcorn[1].gif

Posted by: Chris914n6 May 9 2016, 11:00 AM

Essentially stalled pending a car that wants to be driven headbang.gif
Need to make sure all the pieces work well together before writing $1000 checks.

For your other question, fixed orifice common in the hotrod market. Available in r12 and r134 sizes, so you're covered.

Posted by: timothy_nd28 May 9 2016, 12:11 PM

Do you happen to have any prototype boxes that you are willing to part with?

Posted by: Chris914n6 May 9 2016, 02:50 PM

Only have one working unit. The rest are cardboard... smile.gif

Posted by: Gary May 12 2016, 04:34 AM

I'd be all over one for A/C today if available.

Posted by: Mowog4 Jun 5 2016, 06:07 PM

Has anyone come up with a solution yet? I am looking to buy something in the next couple of weeks

Powered by Invision Power Board (http://www.invisionboard.com)
© Invision Power Services (http://www.invisionpower.com)