I in no way disagree with you there.
440 Overheating 230 degrees
- Thread starter standup303
- Start date
-
I'd be looking at the Chinese aluminum housing, if it's the version with small internal restriction a hi-flow pump could cause cavitation.
standup303
Well-Known Member
Funny thing is I researched the Mancini and 440 Source pump housings and the general consensus was the Mancini housing had the larger passages. So ordered the Mancini housing and the housing had a 440 Source logo on it haha!
standup303
Well-Known Member
I mis spoke on this. I got stuck in traffic coming home from an alignment today and the car stayed at a steady 185. Soon as I started moving the temp kept climbing.
Was at 235 by the time I pulled in the garage, made sure fans were on. I quickly jumped out and measured the surface of the metal top and bottom port on the radiator they were within 5 degrees of each other.
When I got back in the car to shut it off it was back to 185.
Hoping it’s just the t stat not opening. Going to order the Stewart high flow stat today and will report back.
If you have a high volume water pump and not a high volume thermostat, then the water pump cannot pump to full capacity. So a high flow thermostat may help in this case.
Mancini use to sell the Mopar Performance housing.
mopowers
Well-Known Member
At one point, I had three aluminum water pump housings on the bench at the same time. The two from 440 Source and Speedmaster had a flattened outer radius on the driver's side passage (first photo below). These two had noticeably small passages than the one from CVR (similar to Mopar one in bottom photo).
The difference is subtle from the outside, but it's a night and day different in internal passage area. From what I recall, the difference was similar on the passenger side passage too. There just isn't a great way to tell by looking at them other than the circled areas in the photos.
I believe the Mopar version are radiused instead of flat too, for what that's worth.
The difference is subtle from the outside, but it's a night and day different in internal passage area. From what I recall, the difference was similar on the passenger side passage too. There just isn't a great way to tell by looking at them other than the circled areas in the photos.
I believe the Mopar version are radiused instead of flat too, for what that's worth.
Inertia
Well-Known Member
Your rad isn't working, either the flow is near totally blocked to only get a 5* diff if the rad was doing anywhere near it's job .
The pump impeller would have to be spinning on shaft, or a totally plugged hose to reduce/stop the flow.
You have the heat gun, there's a good chance you can shoot the temps of the rad, - about half way down, every coupla inches across the front of the rad, and often find cool/cold patches.
Those cool patches in the rad are plugged tubes, not allowing hot coolant to pass.
The bigger the cool area, the bigger the problem.
Here's a great infra red pix Dana supplied to give you a visual of what's likely going on.
Good luck.
Radiator-Temperature
I am going to try to keep this short. I really don't want this to turn into a bickering match about - aluminum vs copper, thermostat vs no thermostat temperature or degree of thermostat to run have read way to much of it. 1972 Scamp 383, 727 trans w/remote cooler, 3.91 gears, electric fuel...
www.forabodiesonly.com
The question is which one does the OP have, if it resembles the top one it's a problem, at rpm cavitation will occur due to the smaller passage.
MOPAROFFICIAL
If it has tits, it's a liabilititty.
Remove that piece of **** fan shroud. Thank me later
Inertia
Well-Known Member
Agree, removing shroud will improve airflow, allowing rad to shed more heat .
Another frizbee perhaps .
Infiniti Dave
Well-Known Member
At the risk of over simplifying,did you leave the spring out of the lower hose? Been missed plenty of times.
mando440dart
Member
Water pump impeller the opposite direction?
I have been doing research for my 383 and have discovered the following.
Big block without AC has a crank to water pump ratio of .95 meaning the water pump pulley is slightly larger than the crank. It also used a larger OD impeller with 10 blades.
Big block with AC has a crank to water pump ratio of 1.4 meaning the water pump pulley is smaller than the crank. It also used a smaller OD impeller with 6 blades.
i have a pulley set from a 66 383 with AC
Water pump pulley OD 5 1/8
Crank pulley OD 7 1/8
having mismatched water pump to pulley can mess with the ability of the water pump to circulate water
Big block without AC has a crank to water pump ratio of .95 meaning the water pump pulley is slightly larger than the crank. It also used a larger OD impeller with 10 blades.
Big block with AC has a crank to water pump ratio of 1.4 meaning the water pump pulley is smaller than the crank. It also used a smaller OD impeller with 6 blades.
i have a pulley set from a 66 383 with AC
Water pump pulley OD 5 1/8
Crank pulley OD 7 1/8
having mismatched water pump to pulley can mess with the ability of the water pump to circulate water
I had frustrating moments figuring out what to do in this arena so I’ll put out what i did. I reserve the right to be absolutely wrong.
383 4 speed. AC car. Not a real powerful high pressure motor by any means.
5.25 inch water pump pulley (high flow pump) i think it’sa 318 pulley
6.5” crank pulley.
24” aluminum rad with dual fans blowing 3200(?) cfm. Fan 1 comes on at 187 fan 2 comes on at 197. I run a 180 thermostat.
The rad/fan setup is from Entropy.
I dealt with Anthony Bustillos.
On a hot day in traffic i have no worries.
Yes, i spent some coin on the cooling system…
I hear many have a lot of experience getting the stock system to cool. He can build whatever you want it seems. Mine is a two row with 1” tubes.
$0.02
383 4 speed. AC car. Not a real powerful high pressure motor by any means.
5.25 inch water pump pulley (high flow pump) i think it’sa 318 pulley
6.5” crank pulley.
24” aluminum rad with dual fans blowing 3200(?) cfm. Fan 1 comes on at 187 fan 2 comes on at 197. I run a 180 thermostat.
The rad/fan setup is from Entropy.
I dealt with Anthony Bustillos.
On a hot day in traffic i have no worries.
Yes, i spent some coin on the cooling system…
I hear many have a lot of experience getting the stock system to cool. He can build whatever you want it seems. Mine is a two row with 1” tubes.
$0.02
Ottoman0331
Member
I have a 74 Duster with 440 that is similar to yours. I recently swapped to a 26in cold case rad with duel fans that came with the rad, 440 source high flow water pump. When driving my car stays around high 190s to 210 (90+ out in SC). The fans aren't the best. They are rated at 1400cfm each. I'm guessing the are way below that. So far the only heat issues I've had is when I run my ac. I plan to upgrade my fans soon. I just need to figure out if I want to go brushed or brushless and find some that fit in the 2.5in I have between shroud and pully. I'm going to have to pick up a high flow thermostat.
The shroud is blocking a good amount of the radiator.
Measure the hight and width of the shroud.
(Assuming both fans are the same OD)
Take the OD and divide by 2 to get the radius (R)
A= π x R ^2
A= 3.14 x RxR
Multiply area by 2 (two fans)
This is the area that air can flow through.
Example:
24x17 ( height and width of the shroud) = 408 sq in
Each fan is 14 inches OD (7 in radius)
Area of one fan opening = 3.14 x 7 x 7 = 153
2 fans = 174 x 2 = 307 sq in
Your shroud is BLOCKING 100 sq in of your radiator. That's 25% of your radiator blocked.
ALSO.
the shroud being a fraction of an inch from the rear of the core and parallel to the core creates a static pressure area where no air flow happens.
You state that in stop and go you are fine but at speed it overheats.
There is your issue right there.
Loose the shroud and the electric fans.
If you search engine overheating you will see a commonality to all the threads.
"My new wiz bang aluminum radiator with cool super dooper custom shroud and electric fans"
You never see "my copper brass OEM radiator with stock mechanical fan and OEM shroud"
standup303
Well-Known Member
Got around to dropping the t stat in some hot water and it did NOT open! Have a Stewart hi flow t stat on the way.
Wow that's a first for me. Was there any signs of damage or misalignment?
1WildRT
Well-Known Member
How Hot was your "Hot Water"...
standup303
Well-Known Member
Measured 200 degrees. 185 degree stat. Didn’t even open a little bit.
standup303
Well-Known Member
Nothing like that. Just didn’t open.
Should be obvious on the gauge when the thermostat opens.
Oldiron440
Big blocks rule small blocks drool!
With castiron heads you need total timing around 37 degrees depending on how much port and bowl work has been performed, I’ve seen heads with very simple unshrouding of the valves need 40 degrees of total timing. So my thinking is that you don’t have enough total timing going down the road, I’d say give it 5 degrees more and see how it effects your overheating problem…
If this works out you will need to lengthen the timing curve in the distributor,
good luck
If this works out you will need to lengthen the timing curve in the distributor,
good luck
Last edited:
I'm not arguing, only stating what I've seen and that ain't it. Most iron headed big blocks I've had experience with settle down at around 32-34 degrees total. I wonder if it's a fuel thing due to location?
-
Similar threads
