Can I ask for some A/C help advice/opinions please...

[RJS]

I recently installed the Classic Auto Air underhood conversion kit :


72 Charger/72-74 Barracuda A/C Performance Upgrade Kit Big Block STAGE-2

My car is a 72 Satellite 400 car with factory A/C but I wanted the Sanden Style compressor and High Efficiency condenser etc... for a few reasons.

Less load on my engine and cooler air from what I'm told.

I may be installing an Air Grabber hood in the future so needed the room too.

I had all my factory stuff rebuilt by Classic 8 years ago but I could see the RV 2 compressor was probably in need of another rebuild by the high side #'s I was getting and the air was cool but not cold air.

****Note I had the driveway resealed so can't take the car out for a few days.*****

So today it's 82 degrees with like 70% humidity and I have (3) 12oz. cans into the system (36oz. total) with these #'s

15 low side and 165 high side, the pencil thermometer reads 43 degrees with windows open A/C set to MAX and fan speed low idling in my garage.


43 degrees is what I get out of my 2020 Buick so am I done or do you believe I may still be a few oz's low with my readings???

I know the complete kits from Vintage Air and Classic with their evaporator usually take 20 to 22 oz's total to be high 30 to low 40 degrees temperatures.

I can't even get a call back or an e-mail answered from Classic Air and have read the other horror stories about the new ownership on here all the time!!!

Thanks for reading this novel!!!
Ron

 

[Curiousyellow71]

How much oil is in the system?

 

[T2R9]

Same kit in my 71 and I also charged it today. I was able to get 30 low, and 200 high with three cans. 40 degrees out the center vent.

Did you put a vacuum on it first and let it sit for a while to verify no leaks?

 

[RJS]

T2R9 I was hoping you would chime in, I saw you in another post with having this kit.
Yes I did the install/change-over about two weeks ago and after crimping the ends and all the work I ran a vacuum for hours 30" and it held after for a day etc... I had initially put in 2 cans 24oz but then my factory (read expensive) heater control valve started to leak so after finding a new one from a very nice guy and waiting on new heater hose i got back to it today and added the additional can. I may be done but with my #'s wondered if I may still need a few more ozs???
Ron

 

[T2R9]

43 degrees with the windows open on max AC is good. Max recircs inside so if you close the windows it should drop more. The weakest point we have on these systems is the weak factory blower fan.

 

[RJS]

43 degrees with the windows open on max AC is good. Max recircs inside so if you close the windows it should drop more. The weakest point we have on these systems is the weak factory blower fan.

yes the factory fan sure can be better, I had mine restored when I did the car in 2015 but not like a new car.

I could have sworn a buddy told me there is a way to boast their power, I'm going to have to ask him about that or maybe I dreamed it!!!
Ron

 

[Darter6]

^^^^^^^ This. 82* and 70% humidity along with the car sitting still Is no to shabby.
Moving 40-60 MPH getting air across the condenser it should drop a few degrees.
I did my old Dodge truck,Sanden and 134. I noticed with the factory charge spec it didn't cool as well as it did with 6oz less.
Same with the truck, slow blower speed even on max. I just installed Vintage Air in my 63 and low blower is faster than the trucks on high.Just a thought.

 

[71RRHI]

Is there any reason why this kit would not work with a 71 RR 383 factory air car.

 

[RJS]

Is there any reason why this kit would not work with a 71 RR 383 factory air car.

I can't think of any reason why, your 71 is the same as my 72 Satellite underhood and interior for that matter!!
Ron

 

[71RRHI]

Thats what I would think. But manufacture list 72-74. I was just wondering why. My A/C worked when I got the car. But stopped blowing cold shortly after. So I know there a leak somewhere. Have been thinking about getting it working again. Not sure if I want to rebuild everthing or do something like this upgrade kit.

 

[bearman]

Red dot has some great fan motors. I have adapted a couple over in some trucks what a difference. Or you could look at the blower fan might be one that would fit that has a better or more fins to pull the air through the evap faster.

 

[1 Wild R/T]

I'd say your a little low...

 

[Some Car Guy]

yes the factory fan sure can be better, I had mine restored when I did the car in 2015 but not like a new car.

I could have sworn a buddy told me there is a way to boast their power, I'm going to have to ask him about that or maybe I dreamed it!!!
Ron

I had a 77 truck that was running the fan off a generic switch when I got it. Blew hard

just got the 69 GTX working. When I jumped the fan to test, it blew like a hurricane. I traced the wires and found them melted at the resistor. Got a new one of those, thought high speed would be the full 12 volts and it’s obviously not. Total disappointment. First old car with working ac and I know the fan blows(no pun intended)

When I have a chance to work on it again I’m going to study bypassing the resistor and just using the factory switch as an on off for 12 volts.

 

[1 Wild R/T]

I had a 77 truck that was running the fan off a generic switch when I got it. Blew hard

just got the 69 GTX working. When I jumped the fan to test, it blew like a hurricane. I traced the wires and found them melted at the resistor. Got a new one of those, thought high speed would be the full 12 volts and it’s obviously not. Total disappointment. First old car with working ac and I know the fan blows(no pun intended)

When I have a chance to work on it again I’m going to study bypassing the resistor and just using the factory switch as an on off for 12 volts.

Feed the blower through a relay.... Use the existing high speed to trigger the relay, feed the medium speed through the current high speed connection & move the low speed to the medium connection....

The original low speed setting it so slow you might not even know the fan is running... So using the original medium as low works well & as you know the original high isn't very fast either so making it medium works well...

On the relay hook pin 30 to the output of the alternator.. 87 to a Tee at the fan connection.. 85 gets grounded & 86 gets fed from the highspeed signal from the switch....

 

[RJS]

Feed the blower through a relay.... Use the existing high speed to trigger the relay, feed the medium speed through the current high speed connection & move the low speed to the medium connection....

The original low speed setting it so slow you might not even know the fan is running... So using the original medium as low works well & as you know the original high isn't very fast either so making it medium works well...

On the relay hook pin 30 to the output of the alternator.. 87 to a Tee at the fan connection.. 85 gets grounded & 86 gets fed from the highspeed signal from the switch....

WOW that's some good information right there!!!
yes he did mention about installing a relay so with this information I'll also pick my buddy's brain to see what he was speaking about too.
TY Ron

 

[Curiousyellow71]

Post 2..I asked how much oil your running because one sign of not having enough oil can be low pressure readings while still blowing really cold. Compressors often come with oil but others do not. Most Sandens compressors come with enough oil they should be ok on a new system. Problems occur when components are added that increase refrigerant capacity or replaced and no oil is added back into the system. When their isn't enough oil... the AC can really crank out the cold until is siezes up from not enough lubrication. To much oil added then their isn't enough refrigerant in the system and it will perform badly. I hope your fine, but it stinks to fry a compressor from not enough oil. Don't ask how I know.Lol

 

[T2R9]

Feed the blower through a relay.... Use the existing high speed to trigger the relay, feed the medium speed through the current high speed connection & move the low speed to the medium connection....

The original low speed setting it so slow you might not even know the fan is running... So using the original medium as low works well & as you know the original high isn't very fast either so making it medium works well...

On the relay hook pin 30 to the output of the alternator.. 87 to a Tee at the fan connection.. 85 gets grounded & 86 gets fed from the highspeed signal from the switch....

Great information. I have relays on the headlamps and concealed doors but never thought to do this to improve blower performance so I did it today.

Used a relay with a mounting tab and mounted it to the heater box with one one of the resistor screws. Looks stock and man what an improvement. It will make my Carlisle trip even more enjoyable! Thanks!

 

[RJS]

Post 2..I asked how much oil your running because one sign of not having enough oil can be low pressure readings while still blowing really cold. Compressors often come with oil but others do not. Most Sandens compressors come with enough oil they should be ok on a new system. Problems occur when components are added that increase refrigerant capacity or replaced and no oil is added back into the system. When their isn't enough oil... the AC can really crank out the cold until is siezes up from not enough lubrication. To much oil added then their isn't enough refrigerant in the system and it will perform badly. I hope your fine, but it stinks to fry a compressor from not enough oil. Don't ask how I know.Lol

Since all was new I can only say whatever Classic put into the compressor.
Ron

 

[T2R9]

Classics instructions specifically state not to add oil so I think your OK there.

 

[Darter6]

Thank you for that. Looks like the truck will be getting a relay.
Did the foam flush on the air box Evap/Heater core that helped allot.