Discussion in 'Classic Mustang Specific Tech' started by oldjudge, Dec 15, 2003.

  1. 65 fastback with 289 bored 30 over and a cam, have installed a new 4-core in; new thermostat and water pump from auto zone, but still tries to overheat in traffic. Any suggestions? Thanks for any ideas.
  2. couple of questions:

    What thermo temp are you running?
    Do you have a fan shroud?
    How far away from the radiator is your fan?

    I went nuts trying to figure this out with mine. Had the heads rebuilt, new water pump, new thermo, new radiator, still overheated in traffic.

    It stopped happening when i realized that my fan was about 3 full inches away from the radiator and basically it was like not having a fan at all. I installed a larger spacer and got the fan within an inch or so and now shel cools like she is supposed to. Hope this helps.

    p.s, if you have a shroud your fan blades should be half way inside the shroud to be effective. If you can see the entire blade when looking down at the shroud, your fan is too far away from the rad.
  3. I Am Running A 195 Thermo Now, I Had A 180, But Changed For Winter, Although Was Still Heating Up With 180. I Do Not Have A Shroud And My Fan Is About A Inch And A Half Away From Radiator. Don't Know If Shroud Will Help Enough Or If I Have To Go Electric Fan?
  4. fan shroud should fix it :nice:
  5. There is one possibility not mentioned.....auotzone may have screwed up and gave you a water pump designed to rotate in the opposite direction....if adding a fan shroud doesn't help...than I would take a closer look at the water pump.
  6. Agreed!

    If it's only heating up in traffic, then it's not a problem with amount of coolent flow. If she was overheating on long steep hills... then I'd consider looking at the pump.
  7. To me, replacing the fan with a good electric one would be a good mod anyway.

    Also, just curious tho, I don't understand about changing the thermostat for the winter. Just didn't think it's necessary. :shrug:
  8. :bang: Fan shroud will make a big difference. It pulls air thru rather than just beating it around. To late now but an Aluminum radiator will drop temps some also. I don't like electric fans I had one shut down going down the interstate in the summer and that sucked. Get a good pitched fan.
  9. Out here in Vegas, we are constantly trying to find efficient cooling for the 65-66 cars. Making sure the other guys issues here have been addressed and no solution has been found, we suggest a 3 row high flow if you wish to keep the 17" stock appearance.

    Some other ideas that you may consider if the stock issue is not a problem. Some people are cutting the core support and using the 67-68 20" aluminum radiators.

    We took it one step further and just welded the 67-68 core support to the car, and went to a Griffin Alum 24" with saddle brackets. This is the extreme way to go but aluminum is way more efficient!

    No matter how you look at it, the 65-66 17" hole is way to small for a high performance small block..
  11. Larger radiator would be for an overheating problem under load, not idleing. At Idle it's an air flow problem.

    Get a good fan blade and a shrowd. That should handle it. The thermostat temp should not matter. once you hit it's opening temp, it stays open. I run 195's in all my cars year round and have never had a problem. I am in the N.East though. Not sure about you guys in the real hot stuff. But the theory should be the same regardless of the outside temp.
  12. The reason for changing thermostats is to get better heat in winter. I am using a stock 4 blade fan, does anybody have any suggestions on a better one they've had better luck with.
  13. I have to disagree with you on that one. I too used to think that I had to cut open my radiator support to get a large enough radiator for proper cooling, but I proved myself wrong.

    I added a griffen bolt-in HD aluminum radaitor and a spal 16 elec puller fan into my 65 to cool my VERY high performance 408 Cleveland stroker. The temp gauges never even gets to halfway so matter how long I sit in one place (ie traffic) and idle.

    I also got this puppy special ordered with a slight modification to the mounting flange that sucked it further into the rad support moving it slightly farther away from the front of the motor so that I had more clearance in front of the water pump:

  14. I have a flex fan I am not using anymore that I will sell you cheap ;)
    You still need to add that shroud though.
  15. Maybe in Maryland! Although the aluminum issue has already been mentioned, come out here where it gets 115 degrees all summer, 100 degrees at night and we'll talk! We play with this issue every summer... "Temp gauge half way?" Is that a h/c gauge?
  16. Not better heat, but quicker heat...
  17. lol - of course its the idiot temp gauge....I spent all my money on the motor ;) so I haven't been able to afford that JME gauge set I plan on putting in yet :nonono:

    However, sitting still on a warm day doing a cam burn in at 1500-3200 rpm for 45 minutes with the electric fan wire to just always run the temp needle barely broke into the standard operating range, so I feel confident enough to drive it out to Vegas and show you this summer ;) ..... if it overheats....I'll be proved wrong and pissed off :(

    Based on your input, an optimum solution to overheating can only be achieved by first addressing location, so if he lives in the Southwest I will seed that climate may be an issue, however, do we know where he lives?

    I do have the benefit of not running any accesories other than an ALt....no air, no power....so I gain a benefit there :D
  18. I have a a/c 65 fastback. She has a shroud and 4row rad. I had a oh problem. I added a flex fan. It helped a little but still overheated. As soon as I had my headers ceramic coated, my over heat problem has gone away. The heat under the hood has been cut in half. This may not work for you but it did for me!
  19. :) I don't doubt you can cool it! I mentioned to him to take notice to everyones comments here which are all good. But the larger the radiator, the more air flow and volume of water = cooler. I was just giving alternatives for all 65-66 cars to make it even cooler and cool down faster. We have the extreme conditions to test this out here.

    Tell you what, let's put your car to the test! Run it down the track once or twice on a hot day, then immediately after, idle the car for a while and tell me if it starts to cool down. If it works, I'll give you the benefit. However, you gotta tell me the actual temp you are running :)
  20. I live in the midwest, where it does get up to 100 degrees in the summer sometimes, however I also have this problem now when it's 40 degrees