67 Mustang cooling

[lifeis4living]

Howdy. Need help making a decision.
Facts: 67 coupe with a mild 302, 2500rpm stall converter with an external cooler. Radiator is 20inch 2 core, recored with a 160 deg, thermostat. Thermo fan is a 16 inch, shrouded unit and blows minimum 2070cfm. At idle engine temp sits close to half.

Questions:Do I suck it and see if cooling system will do the job when car is on the road? Not convinced based on some of the cooling systems I see in cars, but can’t compare apples with oranges.

Do I bite the bullet now before I put the remainder of the front on and reroute the transmission cooler lines, as at present pass they through where one of the deflectors should be, and replace the radiator with a 24inch 3 core?

If so has anyone run lines to an external cooler with a 24inch, 3 core and if so what route did they take?

Appreciate any advice and everyone’s time in advance. Paul 🙄

[Dwayne]

I have a Lincoln 2-speed fan I won't be using if you want a fan that really sucks.

[lifeis4living]

Thanks but If I'm going to upgrade system then would be looking at possibly going to twin fan set up.

[Husky65]

You need a more accurate way of measuring temp first in my opinion, before you spend money elsewhere

[hybrid]

Your current setup might work OK, but personally with cooling I prefer to go on the bigger side because the last thing you want is an overheating car. It ain't fun.

I'm running a 24" radiator with external trans cooler, but mine is a 66 and I have modified the radiator support, so may not be of use to you.

[lifeis4living]

My understanding Hybrid, is the 67's in certain option packages did come out with the 24inch radiators via saddle mount. Provisions are there for original style radiator to be mounted and available. I agree Husky at moment i am guessing so maybe I need to get an aftermarket temp gauge and measure temp before I go spending more money and changing transmission lines set up etc.

Should I replace thermostat with a 180 and is there a ball park figure on what temp is acceptable?

[hybrid]

I use a 180F thermostat and have my fan come in at 90C.

[lifeis4living]

Ok Hybrid well there is something I hadn't thought of. I have my fan set so it comes in when I feel top hose is warming up, i.e thermostat is opening. At end of the day if the fan is running earlier that's not a bad thing right? And does it really matter if airflow while car is moving doesn't cool temp enough to turn fan off?

[hybrid]

Whenever the car is moving, it should have enough airflow so that the fan isn't really required.
Your current thermostat is 160F which is 71C. My ECU is configured to consider 71C to be just out of warmup, where it stops adding extra fuel for cold starts.

Your engine really doesn't need any cooling at all at that point.
You don't want to run too cold, because the oil needs to be at the right point to boil off contaminants and you can harm your engine if this doesn't happen.

[lukep6470]

Hi,

I have a 67 in which I have just installed a 347 over Xmas. I have a cheapie ebay alloy 20inch radiator (Stock size) with the cooling lines from my AOD plumbed into it as well. The rad used the stock inlet/outlet locations. I am running a 92c thermostat and a 70c thremo switch plumbed in to the drain cock location. I'm also using a no name brand thermo fan that is the same size as the core is tall and it doesn't have a shroud.

I'm running EFI so I can measure the temperatures accurately. In traffic the temperature never gets over 95c and on the highway it runs cool enough to cycle the thermostat.

After the engine swap I went for a country run on one of the heat wave days (36 plus) and the driver overheated long before the engine 🌞

I have read somewhere that it is a good idea to cool the trans using the radiator as in cold weather the trans fluid gets up to temperature quicker through the radiator.

[lukep6470]

PS I also have AC, the condenser sits in front of the radiator and is bigger than it. It's never been a problem. I actually had an issue in a 40c day back in November where I wasn't running the fuel pump fast enough and the engine vapor locked due to the heat. I was also running AC on that day and the cooling system kept up.

[lifeis4living]

Thanks guys I will digest. May go for the suck it and see, 180 thermostat better temp gauge option.

[boofhead]

The radiator should be ok. It may not be as there are a lot of factors. Lucky if it is to small then you can get a 24" unit and installed it with no modifications as it is a factory size for the big block. Fan should have no need to run when car is moving along (70k plus?) as the air draw will be higher from the forward movement than what the fan is capable of pulling.

As far as thermostats are concerned, it is there to regulate the temp and effectively set a lower limit for the running engine. The best temp is to have the motor run at 190 deg F so really at 190 thermostat is best - most factory cars have a 195. Now having said that I do like to use a slightly less level aka 180 as I want the temp to drop a little so I have some time before the fans need to come on - I do this to reduce electrical load on the alternator/battery at idle. Saving the 25 amps helps at idle. So I have a 180 thermostat to allow the temp to drop a little when driving so then my EFI turns the fan on at 185 (low speed 15amps) and high speed (25 amps) at 195. I do not remember ever needing high speed fan.

[lifeis4living]

Thanks Boofhead. While ago when I started the car thermos did not kick in as trigger wire to thermo's was disconnected, my bad. Temp rose fairly fast once she had warmed up. Definitely going to put a 180 degree thermostat in for starters ans set fan so it come on after. In terms of using another temp gauge can a sender unit be placed in the outlet of bypass hose, still leaving original in place?

Also is anyone still using the factory radiator deflector or are the just for looks?

[boofhead]

Put the second sender unit in the flow of th water and not at the rear of the engine. So I often use a thermostat housing with a hole drilled and tapped. You can purchase them with the hole already cast into it - which is the best. Otherwise I have also silver soldered in a base fitting into the radiator (copper for alloy weld in a alloy fitting) for the temp or Fan control unit. Lots of approaches available.