07-26-2011, 03:40 PM | #1 |
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The Big Gap
Is this gap causing me a problem?
When I am running down the road my A/C vent temp is 34*. When stopped, the temp comes up to 45* with the motor a 2,000 RPM.at Idle, it is 50*. How should I fix it? I don't think this would be a good solution. My shroud is off of a 2X4 pickup so I used 2 spacers to make the fan reach the shroud since my truck is a 4X4. Would a 4X4 shroud fit better? |
07-26-2011, 03:49 PM | #2 |
VA72C10
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Re: The Big Gap
I don't think it will make any difference in the temp of the air coming out the vent. The compressor is getting turned faster going down the road and air is being forced over the condenser and cooling off the air much better than at an idle. Even in modern vehicles the a/c doesn't cool nearly as well when you're sitting at idle compared to when driving.
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07-26-2011, 03:49 PM | #3 |
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Re: The Big Gap
is it possible you have the wrong mounts for your radiator, maybe 4 core mounts on a 2 core rad....
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07-26-2011, 04:07 PM | #4 |
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Re: The Big Gap
yes that large gap affects negativly how efficiently air is being pulled over your cooling coils by the fan blade
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07-26-2011, 04:17 PM | #5 |
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Re: The Big Gap
To go along with cdowns, the 4x4 shroud is considerably larger and will help both in a/c coil cooling as well as general engine cooling.
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07-26-2011, 04:28 PM | #6 |
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Re: The Big Gap
While I agree a larger and tighter fitting fan shroud will help with radiator and condenser efficiency....aren't his cooling numbers on par for a factory style a/c setup? And isn't the main issue at idle/stop the compressor speed and lack of air over the rad?
If he has no other cooling issues...I don't see how fixing/changing the fan shroud would make an appreciable difference in the temperature of the air coming out of his vents...
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07-26-2011, 05:01 PM | #7 |
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Re: The Big Gap
Wow! 34 degrees is darned near freezing. I've always kept mine in the mid 40's on my a/c vehicles.
Another thing to think about is the insulation of the cab itself. At highway speeds the wind is dissipating a lot of heat from around and under the cab. When you slow down or stop, the compressor slows and the inside air in the cab starts to warm up fairly quickly. The a/c can't cool it down as fast. |
07-26-2011, 05:14 PM | #8 |
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Re: The Big Gap
I have an old A/C book and it says to shoot for 35*.
The shroud is off a 3 core and my rad is a 4 core. Are they different? |
07-26-2011, 05:43 PM | #9 |
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Re: The Big Gap
Yes, 4 core mounts and shrouds are different....also 2wd and 4wd are different on the shrouds. a 4wd shroud is HUGE
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07-26-2011, 05:56 PM | #10 | |
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Re: The Big Gap
Brothers and LMC just list one for 4WD, 3 or 4 core not specified. Are 4WD 3 and 4 core shrouds the same?
Are Brothers or LMC's better quality? Quote:
Nobody specifies 3 or 4 core either. Is non A/C 3 core and W/ A/C 4 core? |
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07-26-2011, 06:05 PM | #11 |
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Re: The Big Gap
Not sure if a 4wd shroud is the same whether it uses a 3 or 4 core rad. My assumption has always been that they are the same....
What I was saying is the upper and lower mounts to the rad support are different for 3 and 4 core rads. On a 2wd bb that uses a 4 core rad it also has a different shroud compared to a truck with a small block and has a 2 or 3 core rad. Not sure if any non-big block trucks came with 4 core rads from the factory or not and if they did whether they would have used the bb style fan shroud or a standard 2wd shroud.. The 4wd shrouds have a much larger area to capture the fan (the round part is much deeper) so that to me is what you need to not only get rid of the gap but also to make sure the fan is well within the shroud properly for optimal cooling But again, I don't expect you'll find much difference in all in the actual a/c output temperatures with a correct shroud vs what you're currently running. maybe a degree or two...but not similar temps compared to when you're at speed....
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Looking for a 67-72 swb or blazer project in or around VA. Last edited by VA72C10; 07-26-2011 at 06:11 PM. |
07-26-2011, 06:12 PM | #12 |
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Re: The Big Gap
You still did'nt say what type of system. Which condenser? Which refrigerant? I can tell you that my 134A-converted factory Four Seasons system is very stable..even at idle but I did all of the necessary sizing and appropriate adjustments to the system and I still have the large gaps like you.
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07-26-2011, 09:30 PM | #13 |
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Re: The Big Gap
50* air on a 90* day sounds nice to me....I aint got no a/c. You a/c guys...somtimes I..!
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