Blueprint 408 cooling system questions.

There is a simple easy way to get an idea of your cooling system's efficiency;
Just measure the coolant temperature before it enters the rad and compare it to the coolant temp leaving the rad. You are looking for a temperature drop between 20 and 30 degrees. Obviously the closer it is to 30* the better.

By my trapspeed, my engine is at 430 hp. My entire cooling system was pirated off a 1973 Dart 318 with A/C, except;
I am running a Milodon hi flow pump with a plate, and
a hi-flow-stat, and a Ford thermostatic fan clutch.
The rad is 37 years old! and is about as basic a rad as be found. It's got patches on it's patches!
My combo has a 4-speed and will pull itself around the parking lot in first gear at 4 mph and less, for hours. The temp gauge never budges.
The minimum coolant temp is 205* at the stat house.
The max is 207* when the clutch fires up the 7 blade fan.
That 367 has no problems spinning that motherfan at 550 rpm, with the timing retarded to 5*BTDC, it never even slows down........
All you guys afraid to run a decent mechanical fan because of the imagined power loss, IMO, well I won't tell you what my opinion is.

Look it's real simple. Throw everything at it and you will get efficiency.
After that, you can start taking away efficiency to your hearts content. But here's the thing, if you can spin the tires all thru first gear, your engine obviously has more power than the chassis can handle. So even if you ascribe some crazy number of horsepower to a direct-drive fan at top-rpm, it matters not one bit when the tires are spinning.

Here is the full-boogy recipe, for testing purposes;
>Proper timing
>half decent fueling
...... at idle this is so easy; the engine is on the low-speed circuit so the mixture screws are all you need, and just run the minimum timing to make it as hard as possible, say oh IDK lemmee guess, how about 14*............. lol
>100% water
> a pump that doesn't cavitate
> a restrictor washer in the stat-house.
> molded hoses
> A fan shroud
> a direct drive 7-blade , hi-attack angle, all steel factory-style fan
> a decent belt, that fits the V-grooves, and that won't slip
> a rad that passes water, where it runs out the bottom hose as fast as you pour it in the top, and that air flies thru the fins, and that is able to create a 30* temp drop thru the rad, at idle, fully stopped.This is the time, for a streeter, that the cooling system is taxed to the max.
> a straitshot at the rad for incoming air. That means no evaporator in front of it . This for a full-boogy system.
> a decent drive ratio
> a hi-capacity oilpan, with extra oil in it for cooling
> a stand-alone oil-cooler for an automatic trans equipped car.

Start at the top and keep building your system until you start seeing a decent temp drop thru the rad. When you get to this point, then you can start back-pedalling; Go back to the top of the list, and start with a coolant mix to fit your climate. Then recheck the coolant drop. And so on.
Tips
>If you take a shortcut and do not see the temp-drop thru the rad; back the heck up.
>If it works at idle, it will work at speed unless your timing and or fueling are out to lunch.
>At idle with no load, your engine will like a lot of timing, easily into the hi-20s and mid-30s. Don't get lulled into thinking that more is better. The transfer-slot sync will dictate you idle-timing. Excessive idle-timing just leads to other issues a lil later in the rpm band. Humor me, just try 12 to 16 degrees. Even the venerable 292/508 cam (the biggest I have tuned) will idle very nicely on 14*, after she gets the bypass air that she craves.
>If all else fails, go look at your skirt clearances and especially the ring gaps.. Retarded timing will cook the rings, and tighten up the gaps. If the engine gets to dragging the rings up and down 3.5 to 4 inches at a crack, that's gonna make some heat. The rings only have three ways to get rid of the heat, which is into the oil, and into the pistons, and into the cylinder walls.