Ten Rules for Maximum Cooling

[Sinitro]

Hmmm.
Often overheating issues are the result of:
a. Lean fuel mixture
b. Incorrect timing

For our legacy Mopars...
Note that I am not a supporter for electric fans,
as adding these require wiring and charging system upgrades
due to the increased amperage of the electric fans. A
couple of electric fans can draw up to 30 amps, pretty close
to the charging capacity of the entire Mopar factory system. Next
turn on the head lites and the total amperage load exceeds
factory limits....

Just my $0.02...

 

[hpg4815]

Hi everyone. I’ve read through all the posts—very insightful, so thank you. I do have a scenario I’d like some perspective on.

I’m running a 440 RB block with FiTech EFI (mentioning this because it hasn’t been professionally tuned yet, and a previous comment mentioned that a lean mixture can cause higher temps). I’m also watching coolant temperature on the FiTech handheld. The car has dual electric fans and a larger aluminum radiator.

On the highway, temps stay around 150–175°F, and in traffic it’s usually 190–200°F. The issue is after I shut the car off: the temperature climbs to around 220–226°F, and I can hear the coolant boiling while the engine is off. The radiator and cap are new. I don’t recall the exact thermostat deg, but the boiling only happens after shut-down. There’s no heater core—those ports are plugged at the water-pump housing—and I have a hose running to an overflow tank.

How can I address the post-shutdown boiling? Is it actually a problem? It bothers me.

 

[33 IMP]

Where are you reading the temperature?
With a decent radiator cap, and coolant mix, it shouldn't be boiling at 225. Or 240.

 

[hpg4815]

Where are you reading the temperature?
With a decent radiator cap, and coolant mix, it shouldn't be boiling at 225. Or 240.

Off the electric fuel injection hand held LCD console. The EFI has a sensor that I have in a port on the back of the intake. Now thinking about it I think I bought the radiator cap. Is there a recommended one?

 

[33 IMP]

Off the electric fuel injection hand held LCD console. The EFI has a sensor that I have in a port on the back of the intake. Now thinking about it I think I bought the radiator cap. Is there a recommended one?

Okay, what radiator? Aluminum or copper/brass.
If aluminum, I'd try to find out what the manufacturer recommends. I'd probably try at least a 15 lb cap. With a good coolant/water mix, it shouldn't boil till 250.

 

[hpg4815]

this is the one I got 75120 Polished Radiator Cap from us radiator. It states Polished Radiator cap. Gm, Ford, Dodge and various applications with Standard filler neck. 16 lbs. for a closed system. 2.20” in diameter. so looks like the cap is fine? I used the Prestone 50/50 Prediluted Antifreeze/Coolant for all vehicles.

 

[RemCharger]

Also not all high volumes pumps are high volume.

While putting a hemi in a RR about 12 yrs ago I ordered a high volume water pump to install and even though it had the flat plate added to the front side of the blades you couldn't see how well the back side of the blades fit to the bevel inside the housing.

I could of used some play dough to check clearance but I had plenty of spare housings and picked a mid 70's left feed housing to cut a window to quick check any pump.

I was disappointed in my new high volume pump and the FlowKooler of the late 90's. I ended up extending the blades on the high volume as it was new and easier to fix than the curved blades of the FlowKooler.

Haven't gone in to see how well the blades are hanging in there sinse the build but the temp gauge seems to say they're still ok. It has a Glen Gray with Max Cool core and the Mercedes/Monster fan with v3 controller.

The high volume had .191 thou clearance to the housing. The FlowKooler was a little better.

Some one in this thread mentioned a lower hose spring, I found a SS spring from a phord site for the lower hose.

Fan runs after shut off for a litte while on the hemi, while my Dart 330 has the mecedes fan also and a remote water pump for flow with the fan after shutoff.

The 475 hemi cools great, the Darts 499 needs a bigger radiator, the 22" is a little small and the fan works harder of which I figured it would but wanted to see if the fan would take up the slack.

View attachment 1945740

View attachment 1945741

View attachment 1945742

View attachment 1945743

View attachment 1945744

Holy crap. That impeller needs to be pulled back of the shaft considerably.