Hemi Swap standard AC

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Ozyduster

Ozyduster

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I am putting a 6.4 hemi into my 74 duster, the duster had factory ac with the 318.
I originally was going to delete the ac however then means i need to play about with the belt system and also having two young kids cruising with no ac may be painful. My other weekender has ac and has come in handy on super hot days.

What do i need to do to get the factory Duster ac to work with the ac compressor that comes with the hemi?
I have had a search and couldn't find info, whats involved from wiring, to parts that need altering or changing.
Currently my entire car is stripped down so i will rebuild the heater box as well.
 
If your motor is in the stock location in regards to the firewall, you will probably need a custom mount.

@JBrian?
 
If you haven't done so already, it may be a good idea to install the engine in the car and also install the heater box to see if any of the connections for the heat or AC interfere with the passenger side head. All four of the pipes for heat and AC come out right where the head will be and even with the engine sitting forward, you may not have ample room for the lines to hook up.
 
Ozyduster said:
No the motor will be forward as i am using the Holley engine mounts
Click to expand...

Oh, my bad. I’ve been following your build and I guess I forgot that.

With the Holley mounts moving the motor forward about 1.75”, the AC compressor is a bolt on. It’s one of the reasons I went with the Holley mounts myself.

Note that it is only a bolt on with ‘11+ motors and since you have a 6.4 you are good. An ‘03-08 motor can’t do it, and the ‘09-10 motors need some parts swapped (I think).
 
JDMopar said:
If you haven't done so already, it may be a good idea to install the engine in the car and also install the heater box to see if any of the connections for the heat or AC interfere with the passenger side head. All four of the pipes for heat and AC come out right where the head will be and even with the engine sitting forward, you may not have ample room for the lines to hook up.
Click to expand...
Yep good tip actually didnt think of the head in regards to the heater pipes. I am dry fitting the motor regardless to make sure everything fits and what holes to meld up so i can then yank it back out and get the bay sprayed. Then just put it straight in no kissing.
Ill get bay, inside and boot all painted so can fit all the wiring loom, motor and dash etc. Then spray the car to try to stop scratches etc. Going to be a slow process
 
Yep
DionR said:
Oh, my bad. I’ve been following your build and I guess I forgot that.

With the Holley mounts moving the motor forward about 1.75”, the AC compressor is a bolt on. It’s one of the reasons I went with the Holley mounts myself.

Note that it is only a bolt on with ‘11+ motors and since you have a 6.4 you are good. An ‘03-08 motor can’t do it, and the ‘09-10 motors need some parts swapped (I think).
Click to expand...
i always put my builds on a forum as then holds me accountable to get them finished haha. Plus honestly if not for forums no way i would have atempted my last build and so many tips and tricks. Also a lot of money saved on parts etc.
 
I'm not sure what compressor is used on the 6.4 What year is the engine? With a lot of swaps, the only thing that needs being done is mounting the compressor (correct compressor for the engine is best), Making new hoses (if the ends don't match the compressor), and connecting the wiring to the compressor (It depends on the compressor). Don't forget to make sure you have engine/condenser fan operation when the compressor is running, even if engine temp does not call for cooling.
 
Charrlie_S said:
I'm not sure what compressor is used on the 6.4 What year is the engine? With a lot of swaps, the only thing that needs being done is mounting the compressor (correct compressor for the engine is best), Making new hoses (if the ends don't match the compressor), and connecting the wiring to the compressor (It depends on the compressor). Don't forget to make sure you have engine/condenser fan operation when the compressor is running, even if engine temp does not call for cooling.
Click to expand...
Not purchased a engine yet as still throwing money at driveline etc haha. Yes it did look as tho people literally just had to put new fittings on to the new hoses to connect to the bulk head fitting etc. However i now cant find parts of my ac system as at the time chucked a lot of it out thinking ill never run that when was going to go turbo 318. So missing a lot of the under bonnet stuff
 
You won’t have any problems with your fire wall. You will have to make custom hoses. You can rent a hose crimper from Autozone and buy all your fittings. If you can get the factory lines from the original donor compressor that may be helpful. As far as you electrical, what harness are you using. I used Hotwire and there is a connection for the compressor. I used a Dakota digital fan controller works great. Use the compressor with the Hemi. If in doubt go to a local A/C shop and ask them. They usually don’t mind giving out free advice. They can also make your lines for you if you want solid lines instead of hoses. I have hoses which I’d don’t really care for, they look messy.
 
I'm running the factory AC in my 69 with the 6.4... I pulled vacuum a few weeks ago and I think I'm in good shape.

I grabbed an aftermarket condenser with built dryer off Amazon and new evap valve, binary switch some special fittings off Cold Hose. Buddy of mine has a hydraulic shop and I got some hose from him did a dry fit, marking the clocking off the fittings with a paint marker. I did have to switch my compressor to the single plug style compressor.. 2015 Jeep or Durango is what I think I used. My harness from Sublime has a AC trigger built in (coinciding with OEM harness) along with relay and fusing. So you just run your AC wire from the dash through through the binary, thermostat (if it has one) and then back to the Sublime trigger. When the trigger is received, it uses the oem 6.4 wiring to kick on/off the compressor.

I don't remember the exact locations of the AC fittings on a Duster but I think they might be a little more forgiving than the 69.. If I'm remembering right. Look through my thread. I'm sure there's some pics. Feel free to ask me any questions.

Compressor
More Information for GPD 6512496
Condenser
https://www.amazon.com/gp/product/B07Z8GQ8Q5/?tag=fabo03-20
 
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