another 360/408 over heating

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A lot of gibberish....

Get an 8 blade impeller water pump "cools better at idle , a 18" flex o lite...more idle/low speed, and good cross flow radiator...step into the 21st century already if you haven't...and set the timing n curve.

If that doesn't work.. you got problems with gaskets or cracked heads.
 
MOPAROFFICIAL said:
A lot of gibberish....
Click to expand...

Wow! Went right straight to the gibberish insult. Come on Man! We are all trying to help diagnose a problem when the problem isn't right in front of us. I could throw insults your way because of your lack in ability to read. He has already stated he's using an 8 vein pump in the initial posting. Do you think so highly of yourself that you can crystal ball the exact fix and you're the absolute end all be all that can be the only one right! ****, I'll save myself the time to think anymore or lend my experience and just hit you up for the one and only correct answer. In my world this is called brain storming. It works very well at solving problems. Quit being a negative Nancy and stop throwing up barriers to effect communication.

There I go getting all snarky again. Sorry.
 
Blind Squirrel said:
When they say 195* that means they fully open at that temperature.
Click to expand...
Sorry, but a 195 degree thermostat STARTS to open at 195. Same with 180, etc. The listed temp is when they start to open.

512Stroker said:
I never had any luck with electric fans for a street application.
I run a Griffin 2 row one inch core radiator with factory 7 blade fan, factory shroud and stock water pump.
My crank pulley is much larger than the water pump pulley, overdriven for factory A/C car.
30 over 340, roller cam with 727 trans runs 180 w/o A/C, 195 with A/C on.
In the past when I ran electric fans I had to divorce the Transmission cooling from the radiator, taking the trans heat load out of the radiator.
Griffin radiators rock!
Good luckView attachment 1715326332
Click to expand...
I have the exact same Griffin radiator in mine. I painted it black and it looks like a stock radiator. At first, I had a flat aluminum shroud with a big electric fan. No matter what I did, the car (375 HP 340) overheated. I eventually got rid of the flat aluminum shroud and went with a stock replacement shroud from Classic Industries, and I installed a fan like Slantsix64 mentioned above. I powder coated the fan semi gloss black first. Works fine now. This is just my opinion, but as long as you have the setup you have now, I think you will continue to have overheating problems.
 
harrisonm said:
Sorry, but a 195 degree thermostat STARTS to open at 195. Same with 180, etc. The listed temp is when they start to open.


I have the exact same Griffin radiator in mine. I painted it black and it looks like a stock radiator. At first, I had a flat aluminum shroud with a big electric fan. No matter what I did, the car (375 HP 340) overheated. I eventually got rid of the flat aluminum shroud and went with a stock replacement shroud from Classic Industries, and I installed a fan like Slantsix64 mentioned above. I powder coated the fan semi gloss black first. Works fine now. This is just my opinion, but as long as you have the setup you have now, I think you will continue to have overheating problems.
Click to expand...
Yup the next time my radiator comes out it will also be painted black.
 
Blind Squirrel said:
Wow! Went right straight to the gibberish insult. Come on Man! We are all trying to help diagnose a problem when the problem isn't right in front of us. I could throw insults your way because of your lack in ability to read. He has already stated he's using an 8 vein pump in the initial posting. Do you think so highly of yourself that you can crystal ball the exact fix and you're the absolute end all be all that can be the only one right! ****, I'll save myself the time to think anymore or lend my experience and just hit you up for the one and only correct answer. In my world this is called brain storming. It works very well at solving problems. Quit being a negative Nancy and stop throwing up barriers to effect communication.

There I go getting all snarky again. Sorry.
Click to expand...
Gawd damn do you have thin skin...lol did i direcrly qoute you or something? NO.
So spare me please. The 'gibberish' line was my replacment for lines of ,mostly, throwing every idea one could possibly toss in the ring...emptying clips just shooting in the darkness. Most of the time the op has another problem hes not aware of...therefore we arnt either. They even may have created a problem themselves... no shroud with the right fan , is better , than one with the wrong fan and poorly designed shroud. I dont even use a fan shroud, had 8.8 dynamic barely running on pump 91 and NEVER had a overhesting issue... in fact, ever since i **** canned the stock style radiator..new or not... i dont have these problems.
I dont have all the answers, never claimed to, just some replies make more sense than others.
 
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harrisonm said:
Sorry, but a 195 degree thermostat STARTS to open at 195. Same with 180, etc. The listed temp is when they start to open.


I have the exact same Griffin radiator in mine. I painted it black and it looks like a stock radiator. At first, I had a flat aluminum shroud with a big electric fan. No matter what I did, the car (375 HP 340) overheated. I eventually got rid of the flat aluminum shroud and went with a stock replacement shroud from Classic Industries, and I installed a fan like Slantsix64 mentioned above. I powder coated the fan semi gloss black first. Works fine now. This is just my opinion, but as long as you have the setup you have now, I think you will continue to have overheating problems.
Click to expand...


Your first statement is exactly correct with the exception of the Stewart Components thermostat. They actually full open by the temp. Every other brand doesn't open until the temp is reached.
 
Regardless of fully open at rated temp or starts to open at rated temp... all thermostats attempt to maintain a temperature, your home thermostat maintains your house temp to within a few degrees of its set point. Your auto thermostat also tries to do the same. If the radiator can transfer more heat than the engine can produce the thermostat will not be open all the way. If the rad can't, the thermostat will go full open and the temp of the coolant will continue to rise until the engine produces less heat. It is that simple.
If you want to know how your thermostat works get a pan of water and a thermometer and test it.
 
yellow rose said:
Your first statement is exactly correct with the exception of the Stewart Components thermostat. They actually full open by the temp. Every other brand doesn't open until the temp is reached.
Click to expand...
Interesting to know. Thanks.
 
Get rid of the 3 row radiator, a big 2 row like the ones from Cold Case will move more air thru the fins than any 3 row radiator on the market. 3 row radiators block more air than they let thru.
 
rod7515 said:
Problem is they are only 9" fans because I had to stagger them around the water pump due to lack of space.
Click to expand...

I redid the calculations based on your 9" fan size

assume 6 holes 3" dia and 2 holes 9" dia

6 x 3" holes total = 42.4 sqin
2 x 9" holes total = 169.5 sqin
total area = 169.5 sqin

22" rad = 21x17 core area (where air can flow) = 357sqin

That results in about 52.5% blockage of air flow at speed.

Assuming your additional holes are 3" you have blocked off 1/2 your radiator.

I challenge anyone to block off 1/2 their radiator and try to keep the engine cool

Loose the shroud, attach the fans to bar stock frame and see how thing go.

Back in the day I had a 63 Econoline, you know the ones with the engine between the driver's and passenger's seat. it started life with a 170 inch 6 and I swapped in a 289 V8. There is no way to put a larger radiator, but I added a 3rd row stock size rad and mounted 1 15" (IIRC) electric fan on the rad, no shroud and it cooled great.


There is a number of things that go into a radiator 1,2,3 etc tubes, the size of the tubes, the pitch of the fins between the tubes, If you have more tubes you have more surface area for the coolant to come in contact with, if you have a finer pitch to the fins you have more surface area for the air to come in contact with (TO A POINT, to fine of a pitch and you obstruct too much airflow)

bottom line... the more surface area the coolant can contact and the air can contact the more heat can be transferred to the air.

Regarding cross flow "modern" radiators... those things are huge, compared to our rads... I have a 3L V6 dodge grand caravan and it has about 30x17 rad core (510sq in). The core is about about 1.25" deep with 2 x 12" fans, the shroud has many areas where it does not cover the rad.
 
Amazing. I'd never have thought of any of this. <rolls eyes>
 
NO time last night to work on car but hoping maybe to have some tonight.
will update as I go .
rod
 
I dont run a thermostat, I use a restrictor plate. Its always open all the time.

No shroud, my fan eletric fan is tight to the radiator but I use one 15 inch fan.

My shroud only made things worse. I was over heating on the freeway but fine at idle.
My shroud was dead heading air.
 
Ive got some updates on my engine heating problem. First let me say before I did any testing tonight I took the car out for a 20 mile drive (again the outside air was around the mid 60's.) with the new 2.75 holes in the shroud. Total of 6 of those holes and they were in the dead head area of my shroud. For the first time the temps stayed lower then in the previous drives and it was a much longer drive. The highest that it got during the drive was 215. When I was moving at 45+ mph the temps would actually run at around 205. As soon as my speed dropped the temp would go to 210-215. The best news was that if they went up I could drive faster and they would come down, but not lower then the 205.
I did not idle the car at all tonight just the drive.
Now for the test results.
Engine hot probably a soak of 170*-180*.
Cylinder Compression Cylinder leak%
#1 150 10%
#2 150 9%
#3 150 9%
#4 150 8%
#5 150 9%
#6 150 10%
#7 150 10%
#8 150 9%

Before I did these tests I removed the fan belt and thermostat and filled the intake to the top with coolant. During the cylinder leak test there were no bubbles in any of these cylinder tests which made me feel much better about a blown head gasket possibility.
While I have the plugs out I thought I would put the pics up and let me hear what everyone thinks of them. They now have maybe 30-35 miles on them and all miles are driven under 3k.

The next 2 pics are passenger side in order 2 4 6 8
DSCN1177.JPG
DSCN1179.JPG


The next 2 photos are the drivers side in cylinder order 1 3 5 7
DSCN1180.JPG
DSCN1181.JPG


To me they might be slightly lean but they are turning a light tan to brown and again they only have 30-35 miles on them. #2 looks a little dark.
I am running a 750 that has been reworked by Sean Murphy in California. He built this for all the specs that I used during the engine build. Im running a mallory fuel pump and regulator. Gauge says its around 6.5-7 at startup but as temps build the fuel pressure drops to around 5 psi? Is this normal. Could heat be vapor locking the fuel feed causing a lean condition. It will act as tho its vapor locked after it gets hot and has sat for 15 minutes. Seems as tho it may even perkulate the fuel. ???? I will be posting in the carb section about setting up a 4 corner carb as I have no experience with one of them at all.

I still need to do a few more tests, first is the radiator flow test that one member mentioned.
I still pan on trying my original 4 blade fan but i dont know if it had a shroud from factory and I dont have one if it did.
I also will be changing out the pulleys and going to a 5" water pump pulley and 6" crank pulley to make the water pump overdriven.
Let me know your thoughts and i will go back and see if I am missing anything I should do that has been mentioned previously.
One last thing, please keep this thread on track for overheating. Greatly appreciated!
Thanks Rod
 
rod7515 said:
Ive got some updates on my engine heating problem. First let me say before I did any testing tonight I took the car out for a 20 mile drive (again the outside air was around the mid 60's.) with the new 2.75 holes in the shroud. Total of 6 of those holes and they were in the dead head area of my shroud. For the first time the temps stayed lower then in the previous drives and it was a much longer drive. The highest that it got during the drive was 215. When I was moving at 45+ mph the temps would actually run at around 205. As soon as my speed dropped the temp would go to 210-215. The best news was that if they went up I could drive faster and they would come down, but not lower then the 205.
I did not idle the car at all tonight just the drive.
Now for the test results.
Engine hot probably a soak of 170*-180*.
Cylinder Compression Cylinder leak%
#1 150 10%
#2 150 9%
#3 150 9%
#4 150 8%
#5 150 9%
#6 150 10%
#7 150 10%
#8 150 9%

Before I did these tests I removed the fan belt and thermostat and filled the intake to the top with coolant. During the cylinder leak test there were no bubbles in any of these cylinder tests which made me feel much better about a blown head gasket possibility.
While I have the plugs out I thought I would put the pics up and let me hear what everyone thinks of them. They now have maybe 30-35 miles on them and all miles are driven under 3k.

The next 2 pics are passenger side in order 2 4 6 8
View attachment 1715328654 View attachment 1715328655

The next 2 photos are the drivers side in cylinder order 1 3 5 7 View attachment 1715328656 View attachment 1715328657

To me they might be slightly lean but they are turning a light tan to brown and again they only have 30-35 miles on them. #2 looks a little dark.
I am running a 750 that has been reworked by Sean Murphy in California. He built this for all the specs that I used during the engine build. Im running a mallory fuel pump and regulator. Gauge says its around 6.5-7 at startup but as temps build the fuel pressure drops to around 5 psi? Is this normal. Could heat be vapor locking the fuel feed causing a lean condition. It will act as tho its vapor locked after it gets hot and has sat for 15 minutes. Seems as tho it may even perkulate the fuel. ???? I will be posting in the carb section about setting up a 4 corner carb as I have no experience with one of them at all.

I still need to do a few more tests, first is the radiator flow test that one member mentioned.
I still pan on trying my original 4 blade fan but i dont know if it had a shroud from factory and I dont have one if it did.
I also will be changing out the pulleys and going to a 5" water pump pulley and 6" crank pulley to make the water pump overdriven.
Let me know your thoughts and i will go back and see if I am missing anything I should do that has been mentioned previously.
One last thing, please keep this thread on track for overheating. Greatly appreciated!
Thanks Rod
Click to expand...
Besides just completely getting rid of that shroud I would also attempt a run at some colder plugs as well..
 
As a test I would take the shround and fans off put the 4 blade on no shroud needed and go for a drive. My bet is your engine stays at thermostat temp while driving and raises at idle due to lack of enough fan blades. My 67 273 has no shroud and a 7 blade fan and runs at temp and can idle all day long.
 
rod7515 said:
Ive got some updates on my engine heating problem. First let me say before I did any testing tonight I took the car out for a 20 mile drive (again the outside air was around the mid 60's.) with the new 2.75 holes in the shroud. Total of 6 of those holes and they were in the dead head area of my shroud. For the first time the temps stayed lower then in the previous drives and it was a much longer drive. The highest that it got during the drive was 215. When I was moving at 45+ mph the temps would actually run at around 205. As soon as my speed dropped the temp would go to 210-215. The best news was that if they went up I could drive faster and they would come down, but not lower then the 205.
I did not idle the car at all tonight just the drive.
Now for the test results.
Engine hot probably a soak of 170*-180*.
Cylinder Compression Cylinder leak%
#1 150 10%
#2 150 9%
#3 150 9%
#4 150 8%
#5 150 9%
#6 150 10%
#7 150 10%
#8 150 9%

Before I did these tests I removed the fan belt and thermostat and filled the intake to the top with coolant. During the cylinder leak test there were no bubbles in any of these cylinder tests which made me feel much better about a blown head gasket possibility.
While I have the plugs out I thought I would put the pics up and let me hear what everyone thinks of them. They now have maybe 30-35 miles on them and all miles are driven under 3k.

The next 2 pics are passenger side in order 2 4 6 8
View attachment 1715328654 View attachment 1715328655

The next 2 photos are the drivers side in cylinder order 1 3 5 7 View attachment 1715328656 View attachment 1715328657

To me they might be slightly lean but they are turning a light tan to brown and again they only have 30-35 miles on them. #2 looks a little dark.
I am running a 750 that has been reworked by Sean Murphy in California. He built this for all the specs that I used during the engine build. Im running a mallory fuel pump and regulator. Gauge says its around 6.5-7 at startup but as temps build the fuel pressure drops to around 5 psi? Is this normal. Could heat be vapor locking the fuel feed causing a lean condition. It will act as tho its vapor locked after it gets hot and has sat for 15 minutes. Seems as tho it may even perkulate the fuel. ???? I will be posting in the carb section about setting up a 4 corner carb as I have no experience with one of them at all.

I still need to do a few more tests, first is the radiator flow test that one member mentioned.
I still pan on trying my original 4 blade fan but i dont know if it had a shroud from factory and I dont have one if it did.
I also will be changing out the pulleys and going to a 5" water pump pulley and 6" crank pulley to make the water pump overdriven.
Let me know your thoughts and i will go back and see if I am missing anything I should do that has been mentioned previously.
One last thing, please keep this thread on track for overheating. Greatly appreciated!
Thanks Rod
Click to expand...


All you can see in your pictures is the car is fat at idle. It's probably all fat all over, but you can't see that with the shells on. Your ignition looks a bit weak, but again, it's a picture that is so far away you can't see anything. I can't even see the heat mark on the ground wire.
 
rod7515 said:
with the new 2.75 holes in the shroud.
Click to expand...
is the 6 x 2.75 holes the same holes in the photo in post #1?

If so I recalculated the shroud blockage to 54% blocked airflow if you added 6 more holes what are the dia of the original 6 holes from post #1

@j par and @yellow rose... enough with the banter, if you two are good friends and joking with each other it is not coming across that way, and it is getting old.
 
they not friends.

Your plug pics are way to far away. To tell.

Timing is read on the part over the electrode. (Ground strap)

Fat at idle is you plugs are black as night on the threads.
Cruze is the porclen part everyone reads.

WOT is down at the base and you need a magnifying glass or cut the plugs to see it.

This is a simple explanation I'm sure YR will expound.
 
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