Cooling question

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70DartMike

70DartMike

Too many projects
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Hey, I've got a question about my cooling system. I'm not necessarily worried about the temp it runs at, however I don't understand why it's running a bit hot.

Here's the deal.

1970 Dart
340, 727, 3.23SG
10.5:1 pistons
Comp Cams 280/480 (????) .. Can't remember specs..
Edelbrock air gap
Holley Street Avenger 670
3000 stall
36 degrees advanced, 8 initial

Champion Aluminum rad, 22" 3 core
180 degree thermostat (tested it in a pot of water, it opened when temp reached 185)
New water pump
New hoses (bottom hose is not collapsing)
Shroud
Tranny cooler
7 blade fan, 3/4" away from rad, far into the shroud

My question is, why is it running steady at 190, then idling at a stop light it will rise to 198 - 200? Without the shroud it'll rise to 210 sometimes.

My cousin runs a 9.5:1 340 with a stock 22" rad, and a 4 blade fan, no shroud, at 180 all day long.

Thoughts??
 
1.....How do you know the temp gauge is accurate?

2.....Just because the stat opens does not mean it opens enough at whatever temp it's regulating/ opening

3....What is the timing doing? Intitial/ total advance?
 
It's an aftermarket gauge with numbers, but I'm not sure how accurate it is?

When I put the stat in water, I tested 2 others at the same time and they all opened at the same time, the same distance. One was new, the others were known to work.

I edited my original post, timing is there.
 
Plus if your comp. figures are correct with yours being 1 point higher than your friends it will run warmer. More comp. more heat.
 
....................give it more time to break in also u should have atleast 12* at idle.....also ur fan needs to be 1/2 and 1/2 with the shroud......kim...........
 
I was gonna say the same thing........you need more initial timing, then you can dial back your idle speed screw a bit.
 
The thermostat does not control a fixed temperature. It will control a bit higher when the heat load is higher (like at idle). It does not open and shut like your home thermostat, instead it is a proportional controller. All of those show "setpoint droop".
 
1968FormulaS340 said:
Your car is not hot. Your car does not have a problem.

The only problem is you THINKING it's hot.
Click to expand...

I'm not concerned with it running at 190, I was just curious as to why its hotter than others around me, even though my cooling system is more advanced.

I am however a little concerned with how much it rises. Today I drove a 1/2 hour on the highway, and idled through a parking lot. Within 5 minutes it crept up to about 212 degrees.
 
I would check it with an infrared temp gun before saying it is too hot.
Had a aftermarket cheapy gauge and it was 30 degrees off.
Temp gun will tell the real story.
 
70DartMike said:
7 blade fan, 3/4" away from rad, far into the shroud
Click to expand...



oldkimmer said:
....................give it more time to break in also u should have atleast 12* at idle.....also ur fan needs to be 1/2 and 1/2 with the shroud......kim...........
Click to expand...


Try this^^^^^^^ If your fan is way recessed into the shroud, that might be part of your issue. Ideally 1/2 in 1/2 out of the shroud.
 
That's a perfectly normal operating temperature. I have much the same stuff and on hot days I run 190 to 200 on the highway and 210 in stop and go.
 
I don't have enough fingers on my hands to count how many times a temp gauge was wrong ...
 
..if your timing is a little retarded you will heat up your heads and coolant.
 
A high idle will cause more heat if you have an inside the radiator trans cooler.
Converters make a lot of heat.

Just a thought I didn't see mentioned.
 
I put a 26 inch 3 Champion rad in my Dart and it cools perfectly! I am not running a shroud and it runs at 185 in traffic and 175 when I am running along. I have a 185 thermostat in mine.
 
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