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OK, riddle me this, I can drive around town (surface streets) for hours and never get over 180*. I drive on the highway/tollway for 10-15 minutes at 3,000 RPM's constant and my coolant temp will gradually climb. I got off the highway today when it hit 195* and it got back down to 180* in about 10 minutes on the surface streets again. I know that this isn't that high to some people, but it was only 62* outside on the way home. I don't want to see what might happen around here in the middle of summer.

Someone had suggested at the speed shop that my Taurus fan was actually fighting against the air trying to come through the radiator. Another guy seems to think since I don't have a hood on the car yet that the air at that speed is not being directed through the radiator (this will be tested soon enough as the hood should be on by this weekend or next).

Cooling System: Edelbrock water pump, two speed Summit Taurus fan, aluminum radiator, and temp sensor mounted in cylinder head.

Thoughts/Commments?
 

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On the highway, you are creating a pressure pocket within the engine compartment which prevents any circulation of air to the radiator. You will correct this with a hood on and as for the electric fan, there shouldn't be an issue at all.

Had that set-up on my 71 back in the day with the exception of a brass radiator and had no prob with the overheating issues with a electric fan and the stock fan shroud.

Hope this helps


Dan
 

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See, now this is the stuff my science teacher should have been talking about back in them schoolin' days.:D

Thanks!
 

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Mine is kinda the same, after several miles at 3500+ rpm it will creep up to 190 or so, but comes right down in traffic. It doesn't like constant high rpm driving. At the track I can get it down to 150° in a few minutes, or sit in traffic in Phoenix in August, but getting there makes the temp climb.
 

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I had that problem for a while. The faster I would go down the highway, the higher my temp would climb. This was after I install a March under-driven pulley system. I put the stock pulleys back on and the temp never climbed above 180.

If your engine is heating up at higher speeds, I'd be looking at the water pump first. I will never again attempt to under-drive my water pump. Any small HP gain there might be from under-driving it isn't worth the price in cooling efficiency.
 

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OK, riddle me this, I can drive around town (surface streets) for hours and never get over 180*. I drive on the highway/tollway for 10-15 minutes at 3,000 RPM's constant and my coolant temp will gradually climb. I got off the highway today when it hit 195* and it got back down to 180* in about 10 minutes on the surface streets again. I know that this isn't that high to some people, but it was only 62* outside on the way home. I don't want to see what might happen around here in the middle of summer.

Someone had suggested at the speed shop that my Taurus fan was actually fighting against the air trying to come through the radiator. Another guy seems to think since I don't have a hood on the car yet that the air at that speed is not being directed through the radiator (this will be tested soon enough as the hood should be on by this weekend or next).

Cooling System: Edelbrock water pump, two speed Summit Taurus fan, aluminum radiator, and temp sensor mounted in cylinder head.

Thoughts/Commments?
Are you running a thermostat? If you dont have a thermostat, the water doesn't have a chance to cool down since its constantly flowing.
 

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Discussion Starter #7
Yes, I forgot to mention, I am running a thermostat. I believe it's a 160* thermostat. I will have to look at the pulley because I believe it is a March set up, but I'm not sure if it's underdriven. Mike gave me all the receipts from when he was building it so I'll have to leaf through them to see what I can find. I like the look of their pulleys, does March offer a non-underdriven pulley if I wanted to stay with those? If it is underdriven I will swap pulleys immediately. I'm also curious to see if it continues to have this problem once the hood is put on. Thanks guys!
 

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1977 Nova 2dr Hatchback, 383/350, 10 bolt-4.11
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I have had this same problem on my 77 even with a 307, 3 core radiator, stock pulleys, 160 thermostat, and 2.73 gears, it would heat up on the road. Drove it from Poteau to Guymon Oklahoma once for work in the middle of July and had to run the heater most of the way to keep the temp down! I tried different water pumps, thermostats, carbs, timing, motors, and always did it, so my thinking it is airflow through the engine compartment.


David
 

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Yes, I forgot to mention, I am running a thermostat. I believe it's a 160* thermostat. I will have to look at the pulley because I believe it is a March set up, but I'm not sure if it's underdriven. Mike gave me all the receipts from when he was building it so I'll have to leaf through them to see what I can find. I like the look of their pulleys, does March offer a non-underdriven pulley if I wanted to stay with those? If it is underdriven I will swap pulleys immediately. I'm also curious to see if it continues to have this problem once the hood is put on. Thanks guys!
Yes March makes what they call "high-flow" pulleys too. I'd go buy one and then I bet your problem will be solved. You might just need the crank pulley.

The fan doesn't do anything at highway speeds so if your car stays cooler at slower speeds and at idle you can pretty-much rule that out.
 

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like pronova said , just change the crank pulley , thats what i did .
your ratio wil be 1:1 or pretty close.
 

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intake

with that sensor on the head , it might even be picking up some heat coming from the headers , i'd try moving the sensor to the intake before you buy anything
 

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Discussion Starter #13
Yeah, I had seen that thread about the location of the temp sensor location. Gonna try the hood first and will update everyone after that. Will measure pulleys as well.
 

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Hey Dennis! Just a reminder, the sensor in the head is for the Taurus fan control. The manual temp guage is at the corner passenger side of the manifold.
If I recall correctly, the water pump pulley is the same as a stock sized pulley.

As for the crank pulley behind the blower pulley, that was supplied by Hampton. It's been a while but I think it is 7 inch pully :confused: Not sure how that would compare to a stock pulley.

Also, it is a 160 tstat.

I'm leaning towards a hood fixing it though...

Ok, back to searching for some new pics of my old car..:D
 

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Discussion Starter #15
Mike!! I figured you would chime in eventually.:D I also think the hood should take care of it and need to make sure as I plan on hitting up the WI leg of the PowerTour here the first week of June. I didn't even realize that about the two different temp sensors and the one for the gauge being in the manifold...thanks for the heads up. As you can see I haven't had to tinker around with the car much. FYI...I'm not sure if you saw the pics I put in the Steering/Suspension section with a couple pics of the new stance after getting the rear springs dearched. It sits pretty mean now, IMO.
 

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I did see them. Looks a 1000 times better than before. Do a search about rolling the wheel wells. I've read of it being done with a wooden baseball bat. That should give you more than enough clearance up inside.

Every so often I drop in and do a search looking to see if new pics of the car have been posted. Unfortunately, I see all the nice Nova's and start to think about doing another....:(
 

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Discussion Starter #17
Actually, what I think I'm gonna do is check the backspacing room I have left to that lower shock mount and may run a 15x7 with 5.5" of BS on the drivers side to "suck" the tire in a little more per ProjectNova's suggestion. If I don't have the clearance I found a local hot rod chassis shop locally and I'm going to have them center the rear end later this year. Got some options for sure, the easiest being running 2 different backspacings to have adequate room on either side. This is what was done to my 71 Nova to deal with the uncentered rear end.

Keep an eye out for some pics coming up in the next month or so with the new hood on. It may not be painted, but it will be on. I'll throw those up in the car profile section.

Take care out there in sunny So Cal!!:D
 

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Discussion Starter #19
Still Doing It...but slower

OK, just picked up the car from the body shop(hood installed & painted) that is about 30 miles away and by the time I got to my exit for work the temp was right at 200*. Drove on surface roads the last mile to work and it came down to about 190*. I know this isn't mind blowing hot or anything, but I don't like seeing the temp north of 195*. Engine RPM was between 2500 - 3000 RPM's the whole time. Now this is an improvement over what it was doing before, but that temp is still climbing at highway speeds. Is it possible that having the timing locked out at 30* all the time could be causing this? That's what one of the guys here at work seems to think.

Any other ideas?

BTW...I will have pics of the hood on the car updated into the car profile section as soon as I get home and get some pics snapped. I forgot to bring the camera with me to work :(
 

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30 degrees

hmm ,, how did you arive to decide to just lock it at 30 ?? The heat its creating is more than the cooling systems capacity is to remove it. Is the sensor still on the head ??? If so which head ?? Sometimes one head will run a lil hotter than the other.
 
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