Cooling Issues

Discussion in 'Technical' started by Maverick392, Jun 29, 2020.

  1. Maverick392

    Maverick392 Member

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    I have a a 392 stroker in my car and have not been able to keep the motor cool while street driving since it was installed. It has a Champion 4 core "Monster" radiator, New Thermostat, and basically new factory style water pump. It's a drag car, so it currently has water in the radiator with a Water Wetter style additive, I know this should probably be changed out for coolant for street driving. The shock towers are shaved for some extra clearance, but I think the engine bay is still a little tight so I removed the hood and did some short-ish drives to test. The car does really good for about 20 minutes of either highway or surface street driving and never gets above 190*. After those 20 minutes though it starts to creep up then runs away regardless of traffic or surface/highway driving. I'm also fairly confident it could use a fan upgrade since the current electrical fan is only rated for 1100CFM. However I've always been of the understanding that at highway speed a fan is irrelevant due to the speed of air coming through the radiator. I know there are a lot of things that could be improved to help here, but I was looking for second opinions, and if anyone could think of why it can drive so nicely for so long then run away like it does.
     
  2. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    1100 not nearly enough; need at least twice that amount. Also, a shroud, if you don’t have one.
     
  3. Maverick392

    Maverick392 Member

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    Thanks for the reply!

    It had a Champion shroud on before but I took it off and actually saw an increase in cooling performance. Knowing that 1100 is not enough, should I still be able to keep cool on the highway at cruising speeds? I've had a lot of conflicting opinions on effectiveness of the fan when driving above 55MPH.
     
  4. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    Welcome to the forum -- from Chicago!

    You having a 392 stroker in a place like Vegas; you going to have to step it up w/ fan size/capacity. I have a slightly moderately modified 302, running stock 2.79 geared, c4. I have,190 stat., 2 row Champion and 16" fan rated approx. 2500 cfm. Once your engine builds up heat, you don't have enough capacity to cool it down, regardless of street or highway. My car will run 190 w/o AC running in most cases, running AC will get me up to 220-230 on 90+ days if idling long periods at train passings.
    I assume your running drag strip gearing producing more heat; w/ the setup u have outlined I don't believe your going to have "cooling" success much of anywhere cept track.
     
  5. Maverick392

    Maverick392 Member

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    What fan do you use? Putting the 4 core radiator in there might have been a mistake, since I now only have about 3.5" of total clearance for a fan without hitting the water pump pulley. The best I've found is a Flex a lite low boy that does 2500cfm and its 3.187" which is about as much as I could possibly feel comfortable in there.
     
  6. Krazy Comet

    Krazy Comet Tom

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    Whether your car will or will not overheat without a fan at highway speeds, depends on how well it pushes through the wind. I don't have any specific info on our cars but I can tell you, pushing air through a four core radiator is akin to pushing a chain, rope etc. Air flow is mostly being deflected.

    You no doubt need a fan with efficient shroud, which means fan should set approx ½ to ¾ way inside shroud.
     
  7. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    The Low Boy is what I am running 8 + years, slightly offset/placed to passenger side of radiator w/ home bru shroud. U need a shroud help pull air when travel slow speeds, idling etc.
    I see if I can find pic on my other computer. Putting Low-Boy in w/ the thick radiator may be a little challenge.
     
  8. Maverick392

    Maverick392 Member

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    Fan ordered. Thanks for confirming some of my suspicions. I'll update after the install. Why is pushing air through a 4 core radiator worse than something with fewer cores? On a side note, where in Chesapeake are you? I lived in Portsmouth for about 5 years.
     
  9. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    You might want to post your car in the "Garage" section of the forum -- Give a few details --We like seeing new stuff!
     
  10. Krazy Comet

    Krazy Comet Tom

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    As far as pushing air through radiator, thick & close spaced cores are almost like a brick wall. Unless there is also a puller, pusher fans are very inefficient.

    I'm near Battlefield Blvd, not far from Greenbriar, prior lived in Deep Creek several years.
     
  11. 71gold

    71gold Frank Cooper Supporting Member

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    :Welcome:...:Handshake:
    your 4 row radiator and the low CFM fan may be a lot of your problem. the 4 row has a lot of restriction plus the fan. the two together acts like a wall.
     
  12. Jaybee

    Jaybee Member

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    Hmm, seems odd that it heats at highway speed. Are you sure the water pump is a good one? I've seen the impellers erode until they don't pump well.

    I'm up in Western Branch, only a few minutes from Suffolk Harbour View area. We've been here 14 months and my wife still hasn't figured out when she sees Greenbrier we're half an hour away.
     
  13. Maverick392

    Maverick392 Member

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    The water pump was replaced a couple years ago with an o'reileys special and the car hasn't been used much since. The last couple of months have seen more mileage than the last 7 years. the fan thats on the car is currently set up as a puller, but will probably end up acting as a pusher when the new Low Boy shows up. I lived on Hatton Point right there in Western Branch haha.
     

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