[hottrodd]

I have a 67 gto factory a/c, all a/c components were replaced or rebuilt, a/c sys. Was vacuumed , charged with 134r., BUT the car a/c will not blow really cold air!!!
Example today it is 85 degrees outside, humidity 50%. The air coming out the center vent will only go down to 58 degrees, shouldn't it be getting down to 45-50 degrees? Installed a/c manifold gauges low side 50psi high side 240psi which is where that should be.,
Or is this all I should expect from a factory a/c sys. Converted to 124r?

[Gator67]

Should blow colder. We run 134 in my wife's 68 FB with stock components and if I recall correctly I get low to mid 40's

[fyrffytr1]

Are you using a stock radiator fan clutch? If it is weak or not working that can cause problems with the A/C cooling.

[lust4speed]

Original POA valve or the POA replacement tube? Pressures are different for 134A to allow the system to operate at the best cooling. The tube is supposed to be a cheap fix since it cycles the compressor on and off when specific pressures are met.

I tried the 134A with the POA replacement tube in the '67 GTO and hated the results. Changed back to R12 keeping the replacement tube, and while things got cooler the system roller-coastered constantly from 36° to 54°. Continuous up and down temps while driving down the highway. Very cool to just comfortable then back to very cool. We moved the amount of 134A up and down, and reset the on/off cycle switch to a higher pressure, but never got rid of the wave. All our adjusting did was move the 18 degree temp swing higher up in the temp range (so we would end up at say 22° to 60°). I finally gave up and went back to the proper POA valve. Now I'm happy with constant 39° vent temps on 100° days. We just couldn't improve on the stock system running stock Freon.

[hottrodd]

I installed poa eliminator, I'm really hating this a/c sys, I'm going one more a/c guy to get his opinion, if he can't fix the temp issue, I think I may go back to r-12, car as of now will only cool to 25 degrees cooler than outside temp, makes no sense,

[69Farburd]

Originally Posted by lust4speed

Original POA valve or the POA replacement tube? Pressures are different for 134A to allow the system to operate at the best cooling. The tube is supposed to be a cheap fix since it cycles the compressor on and off when specific pressures are met.

I tried the 134A with the POA replacement tube in the '67 GTO and hated the results. Changed back to R12 keeping the replacement tube, and while things got cooler the system roller-coastered constantly from 36° to 54°. Continuous up and down temps while driving down the highway. Very cool to just comfortable then back to very cool. We moved the amount of 134A up and down, and reset the on/off cycle switch to a higher pressure, but never got rid of the wave. All our adjusting did was move the 18 degree temp swing higher up in the temp range (so we would end up at say 22° to 60°). I finally gave up and went back to the proper POA valve. Now I'm happy with constant 39° vent temps on 100° days. We just couldn't improve on the stock system running stock Freon.

Like Mick, I tried the POA delete tube and absolutely hated it! I never switched to 134 though. I went back to the POA and it cools MUCH better.

[blue67gtoragtop]

I've got the 134a in mine...agree, its never been as cold as it should be. One problem that I have is that it doesn't push enough volume of air through the vents....any suggestions? The fan does speed up from low to high, but nowhere near the air flow of the newer cars....

[69Farburd]

Originally Posted by blue67gtoragtop

I've got the 134a in mine...agree, its never been as cold as it should be. One problem that I have is that it doesn't push enough volume of air through the vents....any suggestions? The fan does speed up from low to high, but nowhere near the air flow of the newer cars....

Blue, Check out this post: http://forums.maxperformanceinc.com/...d.php?t=776735

[Old Goat 67]

J V and others,

Check out this thread on my son's Chebby truck board.
Tells you how to readjust POA valve to work with 134A. Works better they tell me if you change out the core in front of the radiator with a bigger one.

http://louisianaclassictruckclub.fre...php?f=9&t=1729


Charles

[69Farburd]

Originally Posted by Old Goat 67

J V and others,

Check out this thread on my son's Chebby truck board.
Tells you how to readjust POA valve to work with 134A. Works better they tell me if you change out the core in front of the radiator with a bigger one.

http://louisianaclassictruckclub.fre...php?f=9&t=1729


Charles

Here is a test procedure similar to Old Goat's, but you don't have to use the evaporator. It worked well for me.

http://www.autoacforum.com/messagevi...threadid=16311

[lust4speed]

Been there, done that with a larger condenser. Still couldn't get the 134A and the POA replacement tube as cold as it should have been, but I did keep it when we converted back to R12. Sure can't hurt anything. Unit is out of a Lexus 400. I was a little worried about whether the larger footprint would increase engine temps, but they were at or below what they were before installing the new condenser.

Charles, I hadn't seen the video on adjusting the stock POA valve. Would definitely had tried that adjustment while we were trying to get the 134A to cool good. I had seen the other video on testing the POA and did do that test. I think there was a little less than a pound difference between compressed air and the actual Freon after charging the system.