A/C Port Adapters?
07-24-2010, 12:40 AM
#31
Never said I got better results from the conversion. Got as good as. That is what surprised me.
The reason for the conversion was the owner didn't want to spend $23.00 per can of R-12 and figured if he was going to have to top it off later, he'd rather spend the $$ on the cheap stuff.
There really is no difference in the components from a 12/134 on the 928. It's all if it's been properly flushed, new items in the line. It's only as good as the job done on it. I think the pressure issues are more to do with people that are not doing the job properly. I'm still not a fan of 134, but it does work.
The reason for the conversion was the owner didn't want to spend $23.00 per can of R-12 and figured if he was going to have to top it off later, he'd rather spend the $$ on the cheap stuff.
There really is no difference in the components from a 12/134 on the 928. It's all if it's been properly flushed, new items in the line. It's only as good as the job done on it. I think the pressure issues are more to do with people that are not doing the job properly. I'm still not a fan of 134, but it does work.
If you saw a improvement by going to 134A then you have corrected a problem with the R12 system during the change over.
The biggest things are condenser size and humidity from what i have found, once the temps go past about 90 it goes south for 134A from a temp/pressure standpoint.
I did one back to back, r12 to 134a and then back to r12, full flush and drier change, that answered any questions I had.
In traffic around Atlanta on a 95 degree day in a black 928 with 134 is going to be not a lot of fun.
I can not explain why you got better results with 134A if all was equal.
The biggest things are condenser size and humidity from what i have found, once the temps go past about 90 it goes south for 134A from a temp/pressure standpoint.
I did one back to back, r12 to 134a and then back to r12, full flush and drier change, that answered any questions I had.
In traffic around Atlanta on a 95 degree day in a black 928 with 134 is going to be not a lot of fun.
I can not explain why you got better results with 134A if all was equal.
07-24-2010, 12:53 AM
#32
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Never said I got better results from the conversion. Got as good as. That is what surprised me.
The reason for the conversion was the owner didn't want to spend $23.00 per can of R-12 and figured if he was going to have to top it off later, he'd rather spend the $$ on the cheap stuff.
There really is no difference in the components from a 12/134 on the 928. It's all if it's been properly flushed, new items in the line. It's only as good as the job done on it. I think the pressure issues are more to do with people that are not doing the job properly. I'm still not a fan of 134, but it does work.
The reason for the conversion was the owner didn't want to spend $23.00 per can of R-12 and figured if he was going to have to top it off later, he'd rather spend the $$ on the cheap stuff.
There really is no difference in the components from a 12/134 on the 928. It's all if it's been properly flushed, new items in the line. It's only as good as the job done on it. I think the pressure issues are more to do with people that are not doing the job properly. I'm still not a fan of 134, but it does work.
As far as the difference in the components on a 928, you are correct, but there should have been, with the condenser at least and with the safety systems for sure, it should have a tri switch on it, low pressure, high pressure and temp switch.
07-24-2010, 12:56 AM
#33
I understand you now, I can be a bit thick at times, you know that as well as anybody here.
As far as the difference in the components on a 928, you are correct, but there should have been, with the condenser at least and with the safety systems for sure, it should have a tri switch on it, low pressure, high pressure and temp switch.
As far as the difference in the components on a 928, you are correct, but there should have been, with the condenser at least and with the safety systems for sure, it should have a tri switch on it, low pressure, high pressure and temp switch.
Bit OT, but are you making it up to Frenzy this year?
Gezus, we've highjacked another thread.
07-24-2010, 01:00 AM
#34
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Right now I do not know, but we are planning to go.
07-24-2010, 01:01 AM
#35
Great to hear, so are we 
07-24-2010, 01:06 AM
#37
07-24-2010, 11:50 AM
#39
Race Car
If you saw a improvement by going to 134A then you have corrected a problem with the R12 system during the change over.
The biggest things are condenser size and humidity from what i have found, once the temps go past about 90 it goes south for 134A from a temp/pressure standpoint.
I did one back to back, r12 to 134a and then back to r12, full flush and drier change, that answered any questions I had.
In traffic around Atlanta on a 95 degree day in a black 928 with 134 is going to be not a lot of fun.
I can not explain why you got better results with 134A if all was equal.
The biggest things are condenser size and humidity from what i have found, once the temps go past about 90 it goes south for 134A from a temp/pressure standpoint.
I did one back to back, r12 to 134a and then back to r12, full flush and drier change, that answered any questions I had.
In traffic around Atlanta on a 95 degree day in a black 928 with 134 is going to be not a lot of fun.
I can not explain why you got better results with 134A if all was equal.
Dan
'91 928GT S/C
475hp/460lb.ft
07-24-2010, 11:58 AM
#40
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Cool we can park them out in the sun for ten minutes while idling and see what happens.
I will bring pressure gauges so you can see just how high the high side gets during a heat soaked idle.
I will bring pressure gauges so you can see just how high the high side gets during a heat soaked idle.
07-24-2010, 12:06 PM
#41
Race Car
A while back I was working on a custom dual parallel-flow condenser that fits the 928 (it was all set up with mounting points and everything, just needed fitting joins brazed to fit the 928 connections), but in the end I just shelved it because at least in my experience, the performance of my R134a converted 928's was good enough to make me have to lower the temps even as a daily driver in the Atlanta heat.
Dan
'91 928GT S/C
475hp/460lb.ft
07-24-2010, 12:21 PM
#42
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I think the 928 has a weak AC system from the start, my Corvette will freeze you out on a 95 degree day from a heat soaked car in about 20 minutes, you will be turning it down, the 928 I rarely turn it off of full cold.
Granted my Compressor is a bit weak, it is going to get changed when I install the five speed and larger condenser.
As bad as I hate after market parts, I may install another fan in front of the condenser.
Granted my Compressor is a bit weak, it is going to get changed when I install the five speed and larger condenser.
As bad as I hate after market parts, I may install another fan in front of the condenser.
No problem, I've been messing with refrigerant systems on different cars for 10 years or so, so I can bring my gauges too. But I know the high-side pressures will be much higher with R134a of course, it is the nature of the different refrigerant. The thing with the 928 is that it has a relatively small cabin, very large condenser and good cooling fans, so even with R134a IMO it is able to do the job properly.
A while back I was working on a custom dual parallel-flow condenser that fits the 928 (it was all set up with mounting points and everything, just needed fitting joins brazed to fit the 928 connections), but in the end I just shelved it because at least in my experience, the performance of my R134a converted 928's was good enough to make me have to lower the temps even as a daily driver in the Atlanta heat.
Dan
'91 928GT S/C 475hp/460lb.ft
A while back I was working on a custom dual parallel-flow condenser that fits the 928 (it was all set up with mounting points and everything, just needed fitting joins brazed to fit the 928 connections), but in the end I just shelved it because at least in my experience, the performance of my R134a converted 928's was good enough to make me have to lower the temps even as a daily driver in the Atlanta heat.
Dan
'91 928GT S/C
475hp/460lb.ft