We'll see. I don't have room to taper it, as it wouldn't be away from the radiator at the edges, and the depth is only 1". From what I've read 1" is the minimum distance from the core to get flow.
I hope it runs cooler at idle, and not hotter at highway speed! It really gets warm every time I get stuck in traffic.

 

Well the shroud didn't help, and as you guessed, it actually ran warmer with it! Drove to the Wed. night drags, and it got pretty hot on the open road. Luckily I had tools and materials with me, and I removed it while I was there and reinstalled the fan.
Gotta figure another way to reduce engine temps, and see if I can get the engine temps down under 210 degrees.

 

Where is your timing at? Try advancing it a little bit. It might help a little. Just a fine line till getting into detenation

 

Oh man, sorry to hear that. Not totally surprised at all about the outcome, but wasn't wishing that on ya either!

 

I've tried the timing all over the place, and I don't get detonation (that I can hear) even if I advance it enough to make it run on when I shut the key off. From my experience, aluminum heads mask detonation, and every car I've owned with aluminum heads didn't have any detonation you could hear.

 

Think I made some progress today! I tore into it, and removed the shroud. Then I pulled off the two large heater cores I had installed ahead of the radiator on the heater loop for auxiliary cooling. I made new mounts and installed the two heater cores under the radiator horizontally, so they would be out from in front of the radiator.
When I got done I refilled the system with the fluid and water wetter I had drained, and for some reason the system took almost another gallon of water. I check the water every time I drive, and it has never been low, but now I'm questioning whether the two heater cores with the connecting loop between them might have had air in them?
After filling the system up, running it, and topping it off, I took it for a drive. It stayed down around 190 all the way, until I got caught in a traffic jam, and then gradually climbed to 210. Got through the jam and running again, and it dropped back down, which is a first. It used to stay hot once it got there, and didn't seem to recover.
I'll get some more driving in over the weekend, and if this works, I'll look at a small racing radiator laying down under the front, and maybe a 2nd fan blowing air through it. If it stays under 200, like it did today, I'll leave it alone and not worry anymore. I can pull over and wait if I get caught in a traffic jam. Not worth overheating to keep moving stop and go.

 

Went to a cruise in today, and the Falcon ran 175-180 going out in the morning, and about 190 in the heat coming home! Looks like I'm getting it figured out, and working again!

 

Glad to hear your getting a handle on the temp. HEAT ALWAYS SCARES ME!!

 

Me too! And this one was really getting hot after the shroud was installed! Anything up around 260 causes excessive engine wear, and I never got close to that. But a couple times it hit 230 by the time I got parked at Beaches/PIR!
Hotrod Eruption Drags at Toutle next weekend! Going up Sat. afternoon to make a couple test runs, then drags on Sunday. Sleeping in the Burb overnight, and roughing it! Should be a blast!

 

Have a great time at Toutle, I'll be at the state fair for the week with my horses.