Anyone's Thoughts on Air conditiong?

+1 for stock routing pics

I too am with Franken on the need for some pics of the stock A/C hose routing system layout:

Franken said:
Larry can you tell me a little about the standard pipework routing? As we never got A/C cars here I don't have any reference point - apart from some fuzzy pictures in the factory manual!

I regularly refer to your system drawing but I'm not 100% clear on some of the hoses run - eg the one from the evap to the frost prevent valve - does that run in the cabin? Down the tunnel? through the sill? And the one from the dryer to the TX valve - does that run over the steering rack? Or under the floor? If you have any photos they would be invaluable also.

Sorry - I know these are probably obvious questions but I'm flying a little blind here!

Someone here mentioned that the compressed side runs from the engine bay down along the tunnel (where the speedo cable is?) then up to the condensor. I think then from the condensor it runs thru the frunk (right side) to the dryer - the entire works covered in a plastic cover - then back under the battery (LH drive cars) thru the top of the rack/pinnion unit and into the passenger foot area. Turns towards the heater box, where it hits the expansion valve attached near the inlet to the evaporator. Return from evaporator goes on the outside of the tunnel (passenger side) back in the spare tire area. I can see there are metal loops unused on my originally non-AC '76. Somewhere between the evaporator and the AC compressor is the frost prevent valve, but I've no idea where.

My donor AC car had half of the components I need removed - only have the AC heater box left. Since I'm doing a K20 conversion, I'm definitely using Larry's information and parts list to make this work, along with a stock K20 compressor.

It would be very useful to see the plumbing routing if anyone out there has it. I've seen that requested in various threads lots of times.
 
I will see if I can do this in the next couple of weeks.

Maybe I can cobble together some images with diagrams. It wont be pretty, but maybe it will supplement the schematic.
 
Frost prevention valve

I too am with Franken on the need for some pics of the stock A/C hose routing system layout:



Someone here mentioned that the compressed side runs from the engine bay down along the tunnel (where the speedo cable is?) then up to the condensor. I think then from the condensor it runs thru the frunk (right side) to the dryer - the entire works covered in a plastic cover - then back under the battery (LH drive cars) thru the top of the rack/pinnion unit and into the passenger foot area. Turns towards the heater box, where it hits the expansion valve attached near the inlet to the evaporator. Return from evaporator goes on the outside of the tunnel (passenger side) back in the spare tire area. I can see there are metal loops unused on my originally non-AC '76. Somewhere between the evaporator and the AC compressor is the frost prevent valve, but I've no idea where.

My donor AC car had half of the components I need removed - only have the AC heater box left. Since I'm doing a K20 conversion, I'm definitely using Larry's information and parts list to make this work, along with a stock K20 compressor.

It would be very useful to see the plumbing routing if anyone out there has it. I've seen that requested in various threads lots of times.

Some of the cars my 87 does not have this valve. The idea here is that when frost is detected a solenoid valve on the return side of the AC in the engine bay closes. This causes the warm liquid freon or 134a to now flow into the evaporator but is not allowed to expand because it is being pumped towards a dead head. When the frost clears, the evaporator and this will happen quickly, the solenoid valve opens and flash expands the liquid refrigerant, returning the system to normal cooling. In standard systems the clutch disengages from the circuit and this allows the ice or frost to melt on the evaporator as air blows through the evaporator. This method is not as fast for clearing the frost but it will not stall the compressor in the case of over charging the system when the solenoid valve closes.

My Abarth X1/9 uses all stock X1/9 parts but uses the Abarth AC compressor. Since I do not have the electronic climate control I use the X's bleed valve to the manifold to adjust MAP pressure for the added load of the compressor when running. The ECU detects the difference so quickly that no change in engine RPM is noticed. Also and a bit off track, the 140 amp alternator under ECU control sees no difference in engine RPM when the head lights or rad cooling fans kick in. The head lights are brighter and the dash VM sits considerably higher.

TonyK.

Grimsby Ontario Canada.
 
Excellent topic

Since I'm rebuilding the Bumble Bee (limoncello) I'm considering putting AC into her. The car originally came with AC but a previous owner disconnected and tossed the pump. I've stripped out a couple of AC X's and re-accumulated the parts. However, like other have said "I've only used it X many times ...".
 
Condenser, condenser, condenser...

(Stolen from real estate agents saying Location, location, location...)

For many moons now I have work on auto, residential and commercial A/C systems here in SoCal and Vietnam... on Yorks, Trane 280 ton units, on old Worthingtons, to the latest Carrier Turbines (back in 1970). On Chryslers and GMs, but never on a Ford, and a few Japanese cars...

All this and I consider myself NO expert... but I do believe the key to efficiency is condensing the refrigerant... as this it where the FUEL is made to absorb heat in the evaporator and where heat is transferred out of the space you are trying to cool.

Sure... all the other components play equal roles... but as many experts have agreed, and where they have made major strides in efficiency is by building larger and more efficient condensers and fans to work with them.

As Franken said, there are limitations of the size of the condenser at least in two dimensions... But a core or two could be added in thickness with no real problem.

All I have said would not be of concern to Tony K as he is having trouble frosting the evaporator... and as he says, more air movement, reduction in the amount of refrigerant, playing with expansion valves or more ambient heat are things that would remedy this. One thing he mentioned also was not using LOW, but medium or high fan speeds.

Alas, in the environment in which many of us live, we would always use high or medium speeds and I have never experienced a frost blockage on a properly engineered and charged system.

I just said all this to say if all were well, I would increase the condensing capability to improve performance.

Good discussion and I am also sure there are 10,000 different ways of going about this.

Continue having fun...
 
As I promised, I drafted up the plumbing

I will post it in a new thread so that it is more easily found via the search function for future reference.
 
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