I'm looking at purchasing a new radiator and Midfifty has a 4 row copper one that is supposed to cool anything you can stuff under the hood of a F-100. The part that has me confused is the fact they say it uses a 7lb cap and I thought that the standard pressure required a 15 lb cap, I'll be running a sbc. Is the 7lb adequate for my application?

 

I am running one in my 56 with a 460, a/c, mech fan, and shroud. I am in Ca. And it keeps real cool.

 

My truck is running a sbc and a four row radiator from Midfifty w/7lbs cap. It cools great even with the a/c.
brian...

 

^^Geez, everybody has A/C in their 56's now....

 

Sure a 7 pound cap will be fine. You should either plan on using a recovery tank or keeping your coolant level a few inches below the cap for expansion.

 

my friend is running a 4 lb cap on a '50 merc with a 283, my 390 in my panel is running a 7 lb cap and my flathead is a zero pound cap. the more system pressure (larger pound cap) the higher boiling point you have.

 

Just don't try to run a 14lb cap on a 7 lb system. Ask me how I know?

 

Thanks, I just want to make sure before I order.

 

when i first got my '47 it had a 4lb cap and you could hear the top tank expanding then contracting when it cooled down.

 

Any explanation to why the different pressures on the radiators, what makes one take a 15lb cap and another the 7lb? I don't understand the theory behind this mystery

 

^The boiling point of water(specifically) increases 3º for every increased pound of pressure put on it.

The equation for coolant is probably somewhat different, but the theory is the same.

Thus, a higher pressure cap means a higher pressure system = higher boiling point of coolant.

 

I just ordered a radiator from Midfifty a couple weeks ago, and got it in last weekend. Drove it the first time this week, but don't have a temp guage hooked up yet. Seems to be fine so far, coolant staying at the same level. Only issue I had was one of the holes was slightly off from the hole in the support frame. A little fileing with a rat tail file and it went right in. The are a couple holes in the bottom for hooking up a tranny cooler I presume, but a couple standard size plumming plugs from the hardware store fit fine.

Here is a question for someone though. I got the radiator to support seal, hood to radiator seal, and the gravel pan seal. Where or how in the heck does the gravel pan seal attach? There wasn't one there before, so I have nothing to compare it to. Right now its just laying on the frame below the radiator.

 

The gravel pan seal was stapled to the gravel pan believe it or not. It was layed on top of the gravel pan in in that dipped down area. I purchased all the seals from Midfifty and the self tapping screws they suggested to install it. I also just placed an order from Midfifty but my radiator is on back order and should shipped out next week.

 

I also used the 4 core from mid-fifty in my 56 f600 with a 5.9 cummins diesel with mech. fan.... I'm in California with no cooling problems.