Even in Vegas, If your truck is climbing at stop lights its likely you have something not functioning properly. The number one failure is usually the radiator cap. I know you said its all new, but have you run a pressure test on the system? I'd check there first before I do much. Be sure and test the radiator cap. Not sure what brand it is but it would not be the first time I saw a defective one from a multitude of parts stores.
CK5
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Every Time I Try to Outsmart GM Engineers, I Get the "smack down" (Fixed)
- Thread starter 1-ton
- Start date
Fred_M1010
1/2 ton status
Is the stock fan shroud intact?
Without that, the fan doesn't do much good.
Without that, the fan doesn't do much good.
I have to reply to this one. Higher flow rate = more heat transfer. There is nothing in an effective cooling system to slow flow rates down, ever. The restrictor plates are to build block pressure to make sure that coolant is fully distributed in the heads and to add a couple PSI to the heads to limit steam pockets. The "slow it down so it has time to cool" thing is so old it has a lot of traction and is way wrong. If you want more heat transfer, speed up the flow rate. You would never put a "restrictor plate" in front of your radiator to "slow down the air so it has time to cool the water" and expect it to cool better, why put it in the water flow? More flow = more cooling
Other than that the OP has been well guided here.
black dawg
1/2 ton status
A good easy cooling upgrade that I have found, is the plastic fan blade found on the vortec 5.7 motors. It bolts right on the clutch with no mods (serp belt tbi motors). Better idle a/c and coolant temps.
I wish I could go with one of those, but I am not sure it will work because my truck was the last year of V-Belt truck that turns clockwise. I think those Vortec fans are for serpentine belt system that turn counter clock wise. The V-belt system on my 1991 V3500 is one of the things that makes my truck a more odd ball truck than any other truck that Chevy ever produced. I am pretty sure that when GM finished production of the 1991 V3500 that they threw away all the documentation on it in the trash.
I think the only reason the 1991 V3500 ever existed was because the Military ordered a bunch, and only a small hand-full became civilian Silverado models like mine. Everything on my truck is a "mish/mosh" of old and new technology of its time. The wire harness on a 1991 V3500 is a one year off basterdisation that only existed for that one model year only.
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If you have time, I'd think you might be able to scrounge one out of a wrecking yard pretty easy, $50 might be in your "not worth my time" category lol.
From what I've been reading (yes, I read all the cal poly etc. testing on automotive cooling systems) increasing airflow is a bigger factor in a radiator shedding heat than how fast the coolant moves through the radiator, although both improve heat shedding. If you have one of the poorer GM fan designs (since there are probably 3, 4, 5, and at least 7 bladed OEM fans) the fan change itself might make a significant difference in cooling. I'd also want to try and approximate the RPM from the original application. I can see low-RPM cooling being a significant problem, and changing fan RPM could have been part of that when GM went with the plastic fan/Vortec setups.
Bit hard to read, but I thought interesting:
Roughly, doubling vehicle speed (airflow)=1000 BTU difference, but it took six times as much coolant flow to equal the same change. So if possible, maximizing airflow is going to be the better bet. Of course even here, variables such as fin design are going to affect results. And more fluid OR airflow never results in lower heat shedding.
Edit: BTW, the opening for air movement through the core support is fixed. Not sure what kind of CFM can "fit" through an opening that size, but I don't particularly see a larger radiator being very effective due to that. GM made it longer on the "hot" side of the radiator, and that was probably done because heat would still be lost even if airflow is less than it is more towards the center of the radiator core, due to the incoming temp of the coolant.
From what I've been reading (yes, I read all the cal poly etc. testing on automotive cooling systems) increasing airflow is a bigger factor in a radiator shedding heat than how fast the coolant moves through the radiator, although both improve heat shedding. If you have one of the poorer GM fan designs (since there are probably 3, 4, 5, and at least 7 bladed OEM fans) the fan change itself might make a significant difference in cooling. I'd also want to try and approximate the RPM from the original application. I can see low-RPM cooling being a significant problem, and changing fan RPM could have been part of that when GM went with the plastic fan/Vortec setups.
Bit hard to read, but I thought interesting:
Roughly, doubling vehicle speed (airflow)=1000 BTU difference, but it took six times as much coolant flow to equal the same change. So if possible, maximizing airflow is going to be the better bet. Of course even here, variables such as fin design are going to affect results. And more fluid OR airflow never results in lower heat shedding.
Edit: BTW, the opening for air movement through the core support is fixed. Not sure what kind of CFM can "fit" through an opening that size, but I don't particularly see a larger radiator being very effective due to that. GM made it longer on the "hot" side of the radiator, and that was probably done because heat would still be lost even if airflow is less than it is more towards the center of the radiator core, due to the incoming temp of the coolant.
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Alcohol injection FTW.
Everything has already been said.
Everything has already been said.
And he does not run a thermostat either.
So it overheats? lol
Would have to try towing with it to see.
I put in a 195 degree thermostat, and it is running solidly at 195 degrees with no fluctuation. At least now that my engine is running up to temp, I have been able to get some drive time in with the engine in 'closed loop' so that the ECM can get some data from the engine, in order to make proper adjustments.
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