hi, I have a 1982 Z28 with a ZZ4, and I wanna know if there's any conversion kits to make the a/c work, if lines need to be replaced and also work using R-134a

 

The original will bolt right up. No need for "conversion" or "kit".

Lines should have all their rubber sections replaced and the metal parts flushed. Evap & cond coils need to be verified leak-free and flushed. A new, or at least reman, compressor should be installed, with PAG oil compatible with 134A. All O-rings in all fittings, and the accumulator/dryer, should be replaced. Orifice tube should be replaced, but not with the stock one; 134A in a GM system needs a larger orifice than the GM 12 system came with, a Frod orange or red one is a better match.

Details are frequently posted in the Cooling section on this forum.

 

I put a zz4 in my 82 and everything bolted up just fine. If you're using the stock carb it will have the A/C idle stuff. If you swap to EFI you won't need to worry about that stuff. Either way all the stock brackets should work.

 

thanks! how could I find part numbers because autozone doesn't have zz4 as an option and google isn't telling me much and there's no such thing as books anymore (at autozone atleast)

 

Just get the parts for the stock lg4 or crossfire engine. What parts specifically do you need?

 

Consider the meaning of this carefully. Not sure how I could have said it any more plainly.

If you have a 82 Camaro, ask for parts for a 82 Camaro. (except of course the orifice tube, which should be for, let's say, 96 Frod Crown Vic)

Any questions?

 

https://cnj.craigslist.org/search/pt...=1~gallery~0~0

Here you go. Go with the CORRECT refrigerant.

 

Correct on needing the Ford orifice tube, but the Ford units are actually smaller than the GM one. 0.071" hole for the White GM and 0.062 for the Red and 0.057 for the Orange. The Blue is 0.067. The Jeep green one is even smaller at 0.052. I have used the Green Jeep one with a compact Sanden low mounted on a LS C10 swap. The little compressor could not pump the refrigerant needed for the GM evaporator and the smaller orifice worked to bandaid the inadequate at idle speed compressor to where it worked well. Orifice tube selection can be a bit of trial and error to find the one that works best with a specific setup. Once you deviate from the factory setup and refrigerant, the OE tube size is often wrong. My goal on orifice tube sizing is finding the unit that keeps the low side pressure as close to freezing on the pressure temperature chart without excessively cycling the compressor at the engines normal cruising speed. If you cruise at ~2,200 rpm @ 70 mph, put a big fan in front of the condenser, hold the engine at 2,200 rpm and watch the manifold pressure gauges. Find the P/T chart for the refrigerant you are using and target a refrigerant pressure corresponding to a temperature of about 28°F and try to find the tube that stays slightly above that point. Set the cycling switch cutout point to about 25°F. The temperature of the actual refrigerant in the evaporator needs to be slightly below freezing to get the evaporator surface near freezing. Once the evaporator starts to build a bit of frost on it, the pressure will drop and the compressor will cycle, melting the frost, preventing freeze up.

Here is a whole list of options

https://www.uacparts.com/legacy/Search/EX/EX_Orifice.html

 

I would not waste my time with R12. I can get R134 just as cold or R152a even colder. Would not surprise me if we are not converting R134a systems to R1234YF soon like the OEMs had to do a few years ago. The YF certainly gets cold, my mom has a Titan with the stuff and it is the absolute coldest ac system I have ever experienced in a factory vehicle, including properly functioning R12 systems. With 109°F and 56% relative humidty across the condenser my 97 GM van blows ~44-46°F at extended idle and 36°F stationary at 1,500 rpm. On the highway it will get down to 30°F out of the vents before the compressor cycles. When I say my GM AC spits ICE out of the vents without using R12, I am not kidding.

 

My 1988 Lincoln Mark VII LSC went down to 35* F on it's CORRECT R12 !

 

35°F is cool, but hang out in a vehicle blowing 29-30°F for a while. It will make your finger tips hurt. I would not call any refrigerant correct these days. R12 is almost impossible to find anyone that will touch it.

 

R1234YF works very well. A couple of my vehicles have this refrigerant and it sure does get cold. It's quite a bit more expensive per pound than R134A though. It sounds like we have a good amount of time before R134A is no longer available for purchase (EPA isn't banning production of the refrigerant like they did years ago with R12), so I don't think we'll need to be thinking about R134A to R1234YF conversions for quite some time, although their PT tables are pretty close and a conversion would likely be possible after confirming the particulars like oil type, seal material, dessicant, etc.

R1234YF works well as a refrigerant and is more environmentally friendly (hense why it is being pushed by the EPA), however it is slightly flammable, so that's the tradeoff.

The commercial and residential HVAC industry is going through the same thing with new refrigerants. We just went from R22 to R410A over the past 15 years and now we're moving toward R32.

 

R1234YF and R152a are slightly flammable. I have a newer window unit with R32 that blows ice cold, but that is alao slightly flammable.

 

Actually the system is not supposed to let the evaporator go below 32* F, to prevent freezing.

 

Actually they are designed to go a bit below freezing on cycling clutch systems. A light layer of frost, causes the low side pressure to drop from less heat transfer, forcing a cycle. I have also watched newer vehicles with electronically variable displacement compressors. The newer vehicles will command target evaporator temperatures well under freezing, then they will back off the cooling a bit every 3-5 minutes to melt any accumulated ice.

 

After recalibrating the adjustable cycling switch, the temperatures can get down to freezing or below and when the compressor cycles the ice melts away. My 97 van hovers around freezing and I could drive it all day long with the vents near that temperature and the compressor cycling without freezing up the evaporator core.

https://youtube.com/shorts/msL17b8np...SrQ6rLpv1O1BuI

 

This is my buddies 93 Yukon, R12 to R134A conversion Sanden, Parallel Flow condenser, NBS GMT800 electric fan conversion, and an older adjustable cycling switch. This is his suction line with the blower on low, before the compressor cycles in ~100°F weather. If you are not getting the lines to look like this and then cycling the compressor to melt the frost off, you are giving up system performance. The cycling switch shuts off the system at about 21 PSI on his truck and turns it back on around 40-50 PSI, plenty of time to melt off any ice built up in the evaporator core.