So I have an 84 Berlinetta that has a R4 compressor. Since you can't find R4 refrigerant anymore and R12 is being phased out, I was wondering how to convert my R4 system to R134a?

 

It can be done successfully if you are careful with the details. https://www.thirdgen.org/forums/cool...sion-here.html

 

you can also use r12a if you want. Works very well.

 

It can be done, but I would crimp up my own AC hoses and adapt over the largest parallel flow condenser that will fit the core support opening. The G-van I did last spring is still ice cold albeit a new cycling switch failed and had to be replaced. It failed in the always run the compressor mode of failure. Discovered even on high blower speed it can easily freeze the evaporator core up on a humid 95F day in about 10-15 miles as the center vent got down to 16F. We have already hit 95F here in Texas.

 

If done properly even without doing a mod to put in a different condenser it should work fine for most people.

Do it properly means replacing the compressor with a new R4 for r134a, new accumulator, change all the o-rings to green (pag oil compatible) flush all the old r12 mineral oil from the lines, condenser and evaporator, change orifice tube then use the r12 to r134a conversion table for weight to charge.

One other thing that many thirdgen owners over look is how well it’s sealed, if your door seals, window seals or hatch leak don’t expect your ac to perform well, like you wouldn’t leave the door to you refrigerator open and say it’s not getting cold right?

Actually I have to do a friend’s iron-z cause the heater box has a hole and the ac sucks and everything is new but when your header is sitting next to your evaporator what do you expect.

 

Depends on the climate where the vehicle is run. In +90F R134a with a factory tube and fin condenser performs very poorly. Does not matter what you do to the system, if it cannot shed heat from the condenser it will struggle to cool.

 

Since it looks like stock replacements from Rockauto are parallel flow you can just add this to my list of parts to replace and now you should be fine.

 

Probably 6mm pico design based off their stock photos rather than parallel flow but still an upgrade from the OE tube and fin. I ran into the same issue on that 1987 G20 finding a good replacement condenser. Not exactly rocket science to build a condenser that will actually mount correctly and is parallel flow but it seems beyond the grasp of the manufacturers and retailers of replacement condensers. Ideally they should be building subcooling parallel flow condensers with a vapor/liquid seperator on one tank and a subcooling row.

 

Not sure what your seeing but to the two I looked at on Rock state parallel flow and from the picture it looks correct and not a piccolo tube design.



I agree with you that a subcooling parallel flow condenser is best, this is why when building a custom setup I like to use a Toyota or Honda condenser that fits the rad support opening some even have the separator built on, my GTA is a complete custom setup with a moster flow parallel with a receiver drier on the liquid (vapor/liquid separator) into a adjustable txv to set the superheat across the stock evaporator, txv so obviously no accumulator anymore, sanden sd8.

 

I looked at the only 2 listings for a 1984 Camaro with a 305 on RockAuto. I am not 100% sure if other years interchange, but I was able to get a parallel flow about 5 years ago for an 87 Firebird V8 car.

 

Okay so good for people to know, I put in 91 5.7 and two are parallel flow replacements, these should work on all years if my memory serves me correct the lines/hoses are the same at the condenser side.