Big block cooling question

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some of the older aluminum water pump housings had a problem with the interior holes being too small.
The new 440 source alum. housings had a problem, if running one u need to check it against a stock factory iron housing. I did , and made adjustments to the inside to match the stocker.
 
I know we're talking big block, but 69 340 Dart has factory underdriven pulleys. I have a 22 inch aluminium radiator with the fan shroud. And a thermostatic clutch fan. No issues. Also i have a 440 with a stock 26 inch radiator and shroud, with a stainless 18 inch fan. March underdrive pulleys. Point is, it might not be the pulleys. I eould do the cheap, and simple stuff first. Remove the electric fan. It's blocking airflow. Get the spring for the lower hose. They do collapse. Mustang suppliers sell them about 10 bucks. Pull the thermostat, and check it with a meat thermometer. I've found they can vary alot from the rating. Then try the clutch fan. It needs to be about 1/2in the shroud, with as many blades as possible. Then might check the WP housing. Some have been known to have issues.
 
I know we're talking big block, but 69 340 Dart has factory underdriven pulleys. I have a 22 inch aluminium radiator with the fan shroud. And a thermostatic clutch fan. No issues. Also i have a 440 with a stock 26 inch radiator and shroud, with a stainless 18 inch fan. March underdrive pulleys. Point is, it might not be the pulleys. I eould do the cheap, and simple stuff first. Remove the electric fan. It's blocking airflow. Get the spring for the lower hose. They do collapse. Mustang suppliers sell them about 10 bucks. Pull the thermostat, and check it with a meat thermometer. I've found they can vary alot from the rating. Then try the clutch fan. It needs to be about 1/2in the shroud, with as many blades as possible. Then might check the WP housing. Some have been known to have issues.

As I `ve said before , big h.p. is going to create more heat than a lesser one. What works on a factory or warmed over 340, or 440 probly won`t work on a hot big h.p. stroker ! The more h.p. , the more heat is produced. There aint many A bodies w/ smaller engine bays than the early ones, or a 67-8-9 barracuda.
 
As I `ve said before , big h.p. is going to create more heat than a lesser one. What works on a factory or warmed over 340, or 440 probly won`t work on a hot big h.p. stroker ! The more h.p. , the more heat is produced. There aint many A bodies w/ smaller engine bays than the early ones, or a 67-8-9 barracuda.
All true, but you should always start with the basics first. Then move on to more involved, and expensive changes.
 
Watching this thread with interest...I'm having cooling issues too with my 440. I'm running an aluminum 2 core rad with puller fan and it's just not getting the job done at all.
I'm getting squeal on hot start sometimes so I suspect the water pump is on the way out. Any opinions on high flow impellers? I'm thinking about trying one.
 
I had a Milodon water pump with a hi flow t stat in my big block, it worked very well.
The key is not to under drive the pump, minimum of 1:1 ratio.
I always get better performance out of a 18 inch 7 blade mechanical fan vs an electric fan.
 
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Watching this thread with interest...I'm having cooling issues too with my 440. I'm running an aluminum 2 core rad with puller fan and it's just not getting the job done at all.
I'm getting squeal on hot start sometimes so I suspect the water pump is on the way out. Any opinions on high flow impellers? I'm thinking about trying one.
I'm getting some stock pulleys I seem to have misplaced my old ones I will update when I put them on
 
Get a Flowkooler pump, high flow t-stat and you should be good.
 
Here's how I keep my 512 ci 12.5-1 comp engine cool
Griffin 26 inch 2 core radiator
2 electric fans in the fan shroud
Fans themostaticly controlled
180 thermostat
Don't use 440 source water pump.
32 degrees total timing
Make sure you are not lean in your carb setting

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I had a Jeep Cherokee Chief brass 3 core rad in my 451/'65 A. It was wall to wall radiator and it worked. Had a 440source AL pump housing but went back to stock and it worked better as they had flow issues.
 
IMTERESTING:
I JUST YESTERDAY , BLUEPRINTED MY ALUM. HOUSING, WHILE I HAD IT OFF TO MACHINE IT shorter , TO ACCOUNT FOR THE MOTOR PLATE. Had to machine the alternator spacers off the same amount. All I had to do to the crank pulley was to remove the spacer that I made back when I put the engine in. I still don't expect much clearance from the new fan clutch and the radiator. This will be the last experiment w/ fans, will use the one that works "worked" best.
Still would like to overdrive the fan a little tho--------------
 
IMTERESTING:
I JUST YESTERDAY , BLUEPRINTED MY ALUM. HOUSING, WHILE I HAD IT OFF TO MACHINE IT shorter , TO ACCOUNT FOR THE MOTOR PLATE. Had to machine the alternator spacers off the same amount. All I had to do to the crank pulley was to remove the spacer that I made back when I put the engine in. I still don't expect much clearance from the new fan clutch and the radiator. This will be the last experiment w/ fans, will use the one that works "worked" best.
Still would like to overdrive the fan a little tho--------------

Cooling help?

cheers
 
some of the older aluminum water pump housings had a problem with the interior holes being too small.

Which was disproved a long time ago as being 'the' source for overheating-issues.
But people rather like to remember myths and forget facts. Not saying the holes were not smaller than stock, but if the holes were actually too small the overheating would show up first with highway driving, not during idling.
Their waterpumps were the problem. The scrollwheel impeller is/was not peddling the same amount of coolant as the stock stamped impellers did.
I've tested it myself with a car that always was on the verge of overheating.
Tried changing housings, didn't help.
Tried a few different waterpumps and found the stock stamped steel impeller worked best and flowed the most coolant.
Maybe the factory did know what they were doing after all? :)

As for the topic-starters problem;
Are you running vacuum advance connected to intake manifold or ported carb?
 
No vacuum is hooked up I put stock pulleys on yesterday am gonna drive it today and see if this works if not next will be a stock water pump
 
No vacuum means hotter running engine. Especially at lower speeds.

Where’s your timing at now during idling?
 
Update I got some stock pulleys from the junk yard the same size went for a ride it got up to 200 at the lights but as soon as I left the light the temp went to 195 quickly as before It wouldn't get below 210 unless I went a couple miles down the road with no stopping
 
Update I got some stock pulleys from the junk yard the same size went for a ride it got up to 200 at the lights but as soon as I left the light the temp went to 195 quickly as before It wouldn't get below 210 unless I went a couple miles down the road with no stopping
Are you positive it is not sucking the lower radiator hose closed?
 
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