71 Dealer insalled AC, What is it worth

[sblake01]

Can the old ones be made to run better, new internals maybe for the old A/C units? You know like keep all the stock appearing componets on the outside with new stuff inside?

Yes. I've done a couple of them using a better condenser and a modern compressor, maybe even a condenser fan but that wouldn't appear 'stock'. You can get the colder but they'll never work as well as a system with a centrally mounted evaporator. Steve mentions that he gets mid 40s at the vent. That's okay but you really need to get colder readings than that to be comfortable in the hotter weather. Like readings below freezing that cause the compressor to cycle. Note the readings I used to get when I had my old 810 and my 78 280Z. The overall performance of those two old systems rival any modern system:

P.S. I tried to sell a couple of those old Yorx 240Z type systems that were left here after doing a couple of conversions. Ended up throwing them away......

Edited May 20, 2010 by sblake01

[steve91tt]

Vent temperature is only half of the equation. The vent temperature in my G37 does not get much below 40F but it moves a huge amount of air at that temperature so it gets the car cold fast. It's basically a heat flow issue. You can increase how much cold comes into the cabin by improving the air flow and/or decreasing the vent temperature. You can also decrease the amount of heat that comes into the cabin by tinting or insulating. I've tried to do all of that but in the end I suspect that I will only be able to make the car tolerable in the Texas heat...time will tell.

[sblake01]

Your G37 has 'climate control' of some form if I'm correct. The speed of the air only helps to a point. Size of and number of orifices is also important. I'm an HVAC and MVAC tech and have done a lot of research on this. The G37 type system is far more efficient not only flows more air through larger openings/ducts etc. but creates more cold within the system itself. Larger hoses, piping, more coils in both the evaporator and condenser, etc. I've not had much luck modifying the old Yorx type systems to do much more than make the car 'tolerable' as you say.

P.S.: I'll bet if you ran the vent temp test on the G37 at the point where the compressor cycles the reading would be similar to the readings I attached.

Edited May 20, 2010 by sblake01

[pwd]

Yes. I've done a couple of them using a better condenser and a modern compressor, maybe even a condenser fan but that wouldn't appear 'stock'.

Sounds like that carpenter who bragged he still used his grandfather's hammer, but replaced the handle twice and the head once. There's not much left of that old A/C!

As far as the York compressor, make it a boat anchor. The Sanden rotary compressor is the only way to go. My '73 had one mounted on the driver's side by the Smog Pump on a cheesy steel bracket, but it's original. One problem with that setup is the run of refrigerant lines to the evaporator and back.

[sblake01]

I'm not sure I get what you're saying. I completely removed one system from a car and replaced it with another sytem provided by the customer. I assurme it was the so called 'MSA' system. The other one I replaced the Yorx compressor with a Sanden SD505, replaced the condenser with on from a 280ZX, and mounted a condenser fan on it. In one case I pulled everything out and replaced, in the other, I replaced the above mentioned parts, and some hoses. In either case, I couldn't give away the left over parts.

[kinfish]

Those York compressors make good boat anchors.

No need to cool anything sitting on the sandy bottom.

Keep 'em away from the Z's.