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Discussion Starter #1
In my 66 I've got a 331 Stroker, Holley Sniper EFI, and 4r70w trans. I'm running classic auto air.
Cooling components
Brand new Champion 3 Core radiator, with SPAL 1516 fan and shroud
180 degree stant thermostat
High Volume water pump with purple ice, 50/50 mix- Yes it's burped.
Derale 13402 Trans cooler bypassing radiator

She's running a bit hot when the AC is on after driving for a while, and even a little warm with the AC off driving for a while. It'll take about an hours worth of driving before she starts getting up over 195.

She was running really hot, and then I put a seperate trans cooler bypassing the radiator. She's calmed down now and on really hot days she's running around 200-205. It's not boiling, but it's got me worried.

If the AC is off, the car will run around 195ish and stay there in slow speeds. If the AC is on in slow traffic she'll get into the 215 range. Ideally, I'd like to be able to just keep the AC on and not worry about the temp.

Currently outside it's about 95 degrees with high humidity. Hitting the highway, takes a mile or so, but the temp gets back down near 195 (with AC on).

I know, the typical upgrade is to upgrade to the larger later year radiator and cutting out the rad support. But, my wife bought me this radiator combo for my birthday, and I've already bought plenty of "2 of the same" at this juncture. Besides, I don't really want to hit her with, "I gotta buy a different radiator after she gave me this as gift". I don't have room for a deeper fan, as I only have enough room between the water pump and the back of the electric spal fan to slip a belt between right now.

What other options are there to reduce temps?
Will a fiberglass hood (which I plan to do anyway) help? In specific the Maeir Racing High Rise Shelby Scoop. (I barely have hood clearance now, and have to run a low profile air cleaner)

Will and Oil cooler help? I was looking at something like this.

What other options are there?
 

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I've read on these forums that 215 isn't "hot" and that SBFs are happiest at 205/210. I hope others (@GypsyR ?) will chime in about how hot is ok, and how hot is "hot."
 
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Discussion Starter #3
I'd love to hear that im overthinking it.
 

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Most modern systems enter the “red zone” about 225/230. These old cars may be a little different but not by much. Because the end goal is still to avoid boiling the coolant.

A couple rules of thumb:
Water boils at 212 roughly and coolant is typically marginally higher
Every pound of system pressure increase from your radiator cap increases boiling by about 3 degrees.
So a 13lb cap takes you to around 250. That’s your theoretical max.

I had a mostly stock 70’s 302 in my last mustang and it ran 200-210 in AZ with no AC. Personally, 215 as a max periodically with AC wouldnt concern me much. Just so long as it didn’t keep climbing.
 

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CT, 215 would not scare me at all. But, if you want more peace of mind, get a big thermal clutch fan instead of the electric, and think about an R model front splash fan to let more air in through the front. LSG
 

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Nope. You don't have an "overheating problem". SBF normal operating temperature is 200*F. The threshold of "overheating" is about 235*F which can be tolerated as long as it doesn't keep creeping up above that. 210-215* stopped or in traffic with the A/C running is pretty much normal and once you start moving it should head back down a bit.
 

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Discussion Starter #7
Thanks!
Would either of the above mentioned help with temps anyway?
 

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215 is perfectly normal. On a really hot afternoon my car sill get up around 235 (if I get on it). I used to get concerned, but if it isn't puking coolant I'm ok.
If your rad support has open areas beside the radiator there are plates available that bolt in on either side of the rad. They cause the shroud to draw ALL the air coming into the front of the car through the radiator. I made my own... not shown here but you can see the spaces they fill.
RadPlates.jpg
 

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Thanks!
Would either of the above mentioned help with temps anyway?
Well, an oil cooler will certainly lower both the oil and coolant temperature by removing heat from the engine but the biggest problem is that since you don't have an overheating problem an oil cooler will probably reduce oil temperature below that where the oil has its best "lubricity" and the ability to "burn off" any contaminants. It's said that the best oil temp is about 230*F.
 

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Discussion Starter #10
215 is perfectly normal. On a really hot afternoon my car sill get up around 235 (if I get on it). I used to get concerned, but if it isn't puking coolant I'm ok.
If your rad support has open areas beside the radiator there are plates available that bolt in on either side of the rad. They cause the shroud to draw ALL the air coming into the front of the car through the radiator. I made my own... not shown here but you can see the spaces they fill. View attachment 760986
761025
 

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Hmmm… FWIW, I'd go a completely different direction with your setup. The 16" SPAL is wasting probably 20% of your radiator, at the corners. It's also too small, even the stock fan was 17".

Your thermostat is too cool, these engines run better, with less oil sludge, using a 190° thermostat.

The trans cooler, pasted directly to the condenser, is reducing air flow to the radiator.

A 7-blade, thermal clutch fan, with a stock steel, or better, the "deep" plastic shroud, would pull a lot more air than the electric. And with the bolted-on shroud, would draw through whole radiator, rather than just part of it.

Unless you are towing a mobile home or Miami Vice boat, the oil cooler is overkill, and the airflow reduction is heating up your engine. The small tank in the radiator would do a better job.
 

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It's an oft-repeated subject here. I've been here along time and have gotten a bit worn down by it and so let others answer. But I do still wonder why do people not believe the factory recommended 192-195 degree thermostat is the correct thing to use?
Lately I've gotten lazy and like to tell people to just read the top result when they Google "optimum operating temperature for a gasoline engine" when they think their engine is running hot. They don't seem to want to believe the same exact information from little old me when I say it.
 

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It's an oft-repeated subject here. I've been here along time and have gotten a bit worn down by it and so let others answer. But I do still wonder why do people not believe the factory recommended 192-195 degree thermostat is the correct thing to use?
Lately I've gotten lazy and like to tell people to just read the top result when they Google "optimum operating temperature for a gasoline engine" when they think their engine is running hot. They don't seem to want to believe the same exact information from little old me when I say it.
I got the answer from a retired Ford engineer. Best mileage, best power, and reduced oil sludge. What's not to like about that?

Ford considered 220° to be the overheat threshold, so I'd say anything up to that might be a concern.
 

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Discussion Starter #14
It's an oft-repeated subject here. I've been here along time and have gotten a bit worn down by it and so let others answer. But I do still wonder why do people not believe the factory recommended 192-195 degree thermostat is the correct thing to use?
Lately I've gotten lazy and like to tell people to just read the top result when they Google "optimum operating temperature for a gasoline engine" when they think their engine is running hot. They don't seem to want to believe the same exact information from little old me when I say it.
Didn't know the oem was 192 until you said it here.

I appreciate you clarifying again. I'll look into all of it, but based on what I've discovered here, my temps are fine.

I guess I'm not really understanding how a hotter thermostat would be any different in the conversation of temps getting warm though.
 

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Discussion Starter #15
Hmmm… FWIW, I'd go a completely different direction with your setup. The 16" SPAL is wasting probably 20% of your radiator, at the corners. It's also too small, even the stock fan was 17".

Your thermostat is too cool, these engines run better, with less oil sludge, using a 190° thermostat.

The trans cooler, pasted directly to the condenser, is reducing air flow to the radiator.

A 7-blade, thermal clutch fan, with a stock steel, or better, the "deep" plastic shroud, would pull a lot more air than the electric. And with the bolted-on shroud, would draw through whole radiator, rather than just part of it.

Unless you are towing a mobile home or Miami Vice boat, the oil cooler is overkill, and the airflow reduction is heating up your engine. The small tank in the radiator would do a better job.
Understood. But the trans cooler has actually reduced the overall temp. And I haven't seen mu trans temp over 175 now. Previously it was approaching 200. There's a 1" void between the rad and condensor. Trans cooler is only an 1/8" off condensor.
 

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I had a lot of heating problems. I did everything new radiator, water pump, and replaced all cooling system.

The biggest problem I had was my Edelbrock carb was set way too lean. That causes heat.
Then one day I noticed how badly timing covers and water pumps were cast. The coolant chambers don't align well and choke off the flow of coolant. Not real noticeable to people when you assemble from the outside. BUT. If you take the 2 components off the engine and look at the coolant chambers from the engine side in. You will be amazed and surprised how badly these parts fit. It is pretty messed up. If you explore this you will also agree with me.
Spending some time porting the pump and cover, and cleaning up the casting flash in the timing cover chambers gave me some great results.

I also use Water Wetter. Good stuff.
 
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Much as I hate to say it, again, optimal operating temperature of automatic transmissions is actually 180-200F, Just like a car engine and most other machinery that is lubricated by oil and has a tendency to accumulate moisture inside due to heat cycling. Modern automatics actually have provisions to heat the transmission fluid in order to get it up to temperature quicker. And yes, I know the people who are out to sell you a transmission cooler have these charts that say the cooler you run a transmission, the longer it will last. Basically a lie. Because if you extrapolate from their charts if you cooled your transmission to 40 below zero it would last like a million miles. All the while ignoring the fact that temperature doesn't wear out a transmission anyway, it's the actual use and wear and tear. True enough that running one TOO hot will shorten its life though.

Anyways, don't take it personal, I apologize that it may have come off that way. I'm having a grumpy old man day.

But I will say that if you did not know what thermostat you were supposed to be running perhaps you might want to acquire some service information. A copy of the old factory service manual is a good place to start. Lots of little nuggets of info like that in those things. For those averse to books, PDF formats are available.
 
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Discussion Starter #18
Nah, don't take it personal at all Gypsy.. i tend to listen nowadays.

Anyhow, took her out for an hour drive. Its 84 degrees today. Humidity is down from the past few weeks. Didn't need ac. Stuck and stayed at 192-195 even in stop and go traffic.

Tried romping on her, hitting highway. Driving really slow, all 195 and stayed there.
 

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Most modern systems enter the “red zone” about 225/230. These old cars may be a little different but not by much. Because the end goal is still to avoid boiling the coolant.
 
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