Critique My Front Splitter/Cool Air Intake
03-27-2018, 09:26 AM
#1
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Critique My Front Splitter/Cool Air Intake
03-27-2018, 10:21 AM
#2
with a 50 degree drop I would suspect something else is going on.
Do you have all the seals in place around the radiator to shroud and shroud to hood?
Is your fan clutch working, no leaks no excessive slippage?
No internal blockage in radiator core?
Lower radiator hose isnt collapsing?
Do you have all the seals in place around the radiator to shroud and shroud to hood?
Is your fan clutch working, no leaks no excessive slippage?
No internal blockage in radiator core?
Lower radiator hose isnt collapsing?
03-27-2018, 10:28 AM
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New 2 row aluminum radiator with 1” tubes. Seals around radiator just put in place with no affect on temp. Car cools at idle but creeps up to 240° after 45 min of driving. New water pump on order. Has not arrived. The engine is not the original as I’ve run the numbers so it could be past 30 over and just a hot running engine. Also, the heads have different casting numbers so the temperature sending unit may not be the appropriate for unit for the gauge. The gauge is 37 years old. Lots of variables to still address.
03-27-2018, 10:34 AM
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Its 1/4” plywood covered with truck bed liner. It’s higher of the ground than the oil pan and the transmission cross member. However, I’m considering going to 2 1/2” to 2” of drop for that reason. I’m hopeful if it did make contact the 1/4” plywood would rip away. After Googling, 5 1/2” from the ground is higher than some car manufacturers.
03-27-2018, 12:24 PM
#8
Other causes for running hot
New 2 row aluminum radiator with 1” tubes. Seals around radiator just put in place with no affect on temp. Car cools at idle but creeps up to 240° after 45 min of driving. New water pump on order. Has not arrived. The engine is not the original as I’ve run the numbers so it could be past 30 over and just a hot running engine. Also, the heads have different casting numbers so the temperature sending unit may not be the appropriate for unit for the gauge. The gauge is 37 years old. Lots of variables to still address.
Have you looked at the distributor advance curve?
Is the engine running lean?
You pressure tested the cooling system along with the radiator cap?
03-27-2018, 01:28 PM
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03-27-2018, 05:46 PM
#10
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A repro pace car spoiler made a significant difference on my temps, probably 20-30 degrees difference over just the standard spoiler. I have all the seals intact, a lower hose with a spring in it, a stock replacement water pump and the stock 4 row copper radiator.
03-27-2018, 05:48 PM
#11
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Get rid of the restrictor plate and install a 180 thermostat
03-27-2018, 06:11 PM
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I’ll try it, but like I stated above, it ran cooler with no plate at all. It didn’t have one per previous owner. It never went above 220° without one. I installed one via multiple forums saying some kind of restrictor must be in place to slow the coolant and keep it in the radiator longer. Correct me if I’m wrong but the thermostat opens because of the hot side, so once temp is past 180° It will remain open indefinitely and be no different than a restrictor plate. The thermostat just allows the engine to reach operating temperature faster.
03-27-2018, 06:22 PM
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03-27-2018, 06:26 PM
#14
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A constant transfer of heat from the water the radiator is more efficient at dissipating heat then holding it anywhere ..
Thats why it opens over 180 . it wants to constantly push water past the cooling surface to dissipate heat.
What fans do you have on the radiator ? If ya have a weak fan or fans you will also run hot under load and not so much at idle or light loads.
Thats why it opens over 180 . it wants to constantly push water past the cooling surface to dissipate heat.
What fans do you have on the radiator ? If ya have a weak fan or fans you will also run hot under load and not so much at idle or light loads.
03-27-2018, 06:42 PM
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A constant transfer of heat from the water the radiator is more efficient at dissipating heat then holding it anywhere ..
Thats why it opens over 180 . it wants to constantly push water past the cooling surface to dissipate heat.
What fans do you have on the radiator ? If ya have a weak fan or fans you will also run hot under load and not so much at idle or light loads.
Thats why it opens over 180 . it wants to constantly push water past the cooling surface to dissipate heat.
What fans do you have on the radiator ? If ya have a weak fan or fans you will also run hot under load and not so much at idle or light loads.
03-27-2018, 07:53 PM
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I’m going to try out the thermostat theory. I’m going with the explanation that as the thermostat is closed and the water in the block is heating, the water in the radiator is cooling. After 180° the thermostat opens and they trade places until the thermostat closes again. I’m going with the theory that the radiator cools the water faster than the engine heats it. That has to be the case in order for it to work, otherwise, once the all the water gets over 180° it will never close again and I’m in the same situation I’m in now with the restrictor. It’s a $3 part and a couple minutes to change.
03-27-2018, 08:57 PM
#18
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In my experience, if your shroud is too close to the radiator, it will restrict air flow. The air will flow well right in front of the fan, which is only about 1/3 of the surface. The air coming through the rest of the radiator has a hard time turning sharp enough to make it to the fan. The shroud is good for low speed to make the fan pull air, but at speed, the air flow should exceed what the fan will pull. If your electric fan is right up against the radiator with no shroud, it will work better than one with the shroud too close. A flat shroud like yours would work better if it had flaps that would open when the air flow exceeded what the fan could flow, like at road speeds. Sounds like your splitter will deliver good air flow.
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03-27-2018, 09:25 PM
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In my experience, if your shroud is too close to the radiator, it will restrict air flow. The air will flow well right in front of the fan, which is only about 1/3 of the surface. The air coming through the rest of the radiator has a hard time turning sharp enough to make it to the fan. The shroud is good for low speed to make the fan pull air, but at speed, the air flow should exceed what the fan will pull. If your electric fan is right up against the radiator with no shroud, it will work better than one with the shroud too close. A flat shroud like yours would work better if it had flaps that would open when the air flow exceeded what the fan could flow, like at road speeds. Sounds like your splitter will deliver good air flow.
03-27-2018, 09:28 PM
#20
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The more coolant flow the better it will cool, period. You already proved this by seeing it runs cooler without a thermostat. The fact it won't run cool enough for you means there is a different problem. Some possibilities are the pump isn't producing enough flow, not enough radiator surface area, a coolant restriction in the engine, a restriction to air flow or bad tuning putting excessive heat into the engine.
Since you found more airflow helps, I'd say airflow is the most likely suspect. I would agree with the previous response that your flat shroud restricts airflow at speed. It's likely the increased pressure from your new splitter is increasing the air pressure enough it's both forcing air through the rest of the rad and increasing the airflow hence the efficiency of the airflow through the fan hole.
On a similar note, if you have that fan on all the time it could be restricting the airflow.
Have you tried pulling the shroud and seeing how it does on the highway?
If anyone tells you they did something to restrict the coolant and their car ran cooler then They DID NOT have a flow problem. Something else was the problem. There is a point where you can have too much flow, but for practical purposes you can't reach it with the GM water pump design.
Last edited by lionelhutz; 03-27-2018 at 09:29 PM.
