Comfortable speed

Where is that printed? I would like to read it. G.M.

Ford shop manuals, I have posted it on here many time. Nothing unusual about it, basic engine thermodynamics, it is why all of the manufactures increased the operational temperatures on cars through the years. Internal combustion engines are heat engines and any heat that is lost is power and efficiency loss, so the hotter an engine can be run the more efficient it is. However there are obviously other considerations that limit how far you can go! There was a lot of experimentation going on at one time with the use of ceramic pistons, rings, etc to get the operating temperatures a lot higher, but none of it panned out.

For the Ford example, from a 49-52 truck manual:

"The cooling system used on trucks is the pressure type, having a regulated pressure of 3 1/2 to 4 1/2 pounds maintained in the system while in operation. With this pressure system, the coolant is allowed to reach a higher boiling point. This higher coolant temperature reduces the loss of energy to the coolant and also assists in decreasing internal friction by maintaining a higher lubricating oil temperature."
 
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Thanks to all who responded to my post regarding comfortable speed for the 239 flathead 8 with the 3.78 gears. I am going to let the car tell me what's comfortable but 55 mph sounds about right.

Is the investment worth it for a Columbia 2 speed rear end??
 
When all the systems, steering, brakes etc are in top notch shape 55 is a safe speed. Keep in mind the old brakes are less efficient then new ones which self energize. I myself have a 40 wagon and keep those things in mind while driving by leaving extra room to stop. The wagons I believe are heavier then other passenger cars.

I like to leave extra room to stop, however, others on the roads do not understand that old cars need more time to stop. They pull in to the extra space or pull out in front of you.
 
What would you use to clean out the tubes,small wire brush or some thing
Lawrie

This sounds strange but after using a radiator for years which was in
the 39 conv when I bought it I started using a large bottle of Bars with
aluminum flakes in it because I was getting a little black water when
I started the engine. The dirty water stopped and maybe a year latter
I looked in the radiator with a flash light and the top plate and tubes
looked like I polished them. I took the car over to the radiator shop
drained a little coolant and showed the owner, he never saw a radiator
that clean. This isn't an over night process but it did the job. G.M.
 

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I wouldn't be so sure the radiator is plugged. There is a BIG restriction
in ALL old Ford radiators. There are 144 tubes in most of the old
radiators. These are about two feet long and have a small layer of
dirt on all sides inside the tubes. Also if you add the inside area of
the two top hoses dumping water in the radiator it's as I remember
4.5 square inches, add the area of the 144 tubes and it 3.5 square
inches. This is like putting 3 lbs of whatever into a 2 lb bag. The
coolant don't free flow through the radiator, it has to be forced
through. The restriction causes coolant to back up in the top tank
and out the over flow tube. I don't think Ford added a 4 lb pressure
cap to raise the boiling point, it was added to keep the coolant from
going out the overflow. G.M.

George, Thanks for the 'insight'. This is something I never considered, the total area of the inlet, vs the total area of the tubes. Or, maybe more to the point, the total impedance of one area vs the other. In any event, 3 lb of 'stuff' into a 2 lb bag is certainly a problem. So, what us owners of the non-pressurized era have learned, there is a flow-rate, probably in the region of (the equivalent of) 50 mph, where flow exceeds the free-flow capacity of the tubes. Thanks again, for pointing this out.
And, on another subject, I'm going to try and learn what the Bars product is, with 'aluminum flakes', that produced your 'clean-radiator' results.
Bob
 
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