another 360/408 over heating

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It would really be interesting to see this car go back to the way it came from the factory, cooling wise.
Nice 22" radiator, stock 7 blade fan, 180 thermostat, wire in the bottom radiator hose. 12/34 timming, correct A/F ratio. Simple factory stuff that even cooled an Elephant. If this didnt keep your 408 cool, then something is wrong with your motor internally.

Sure, its hot rodding, but this mad scientist car building has you exactly where you don't want to be. Go back to the basics.
 
I wonder at what point do you stop going back or stop going forward? And this is just for discussion sake. Why not go back to steal manifold why not go back to the stock crank and pistons or not go back to the two barrel or not go back to..
I found customizing one of the funnest parts of my car....
 
j par said:
I wonder at what point do you stop going back or stop going forward? And this is just for discussion sake. Why not go back to steal manifold why not go back to the stock crank and pistons or not go back to the two barrel or not go back to..
I found customizing one of the funnest parts of my car....
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And I can dig that. That's why I mentioned hot rodding.
But I see it time and time again, where guys improve their car into a failure. One of my favorites is the, "Do I need the ballast resistor"? And then the next thread is "why won't my car start" ?

Haven't seen a whole lot of things working for the original poster, maybe stepping back to the basics is the best solution.
 
J par, you posted that once you removed your shroud you do not over heat. Is that sitting still in traffic as well as moving?
Johnny Dart. On post #90 if you go back and read you will see I plan on trying a mechanical fan if there is clearance. Also this car never had a 7 blade fan, the stock one was a 4 blade. Also my timing is at 14/32 as stated in the 1st post so you can be pretty sure that's not the issue.
As for people trying things that aren't factory that's part of the fun of a build. Yes sometimes we may become frustrated and chase our tail but most times we figure it out. I'm not a mopar purist and will never be. I "want" to be able to use electric fans. I personally think they look much better and are much safer plus they dont rob HP. Just my preference.
I dont want the simple things otherwise it would still be a 273 2 bbl.
I've gotten a bunch of really good information from this thread and I'm trying to test not just guess as I work to solving my issue. I also want to document everything as I go so others can see my path to correction and the methods i used.
Thanks for all the help so far, I'm hoping this week I get some time to try the 4 blade fan. If the car then runs cool I will look for another way to make electric fans work.
Thanks Rod
 
rod7515 said:
J par, you posted that once you removed your shroud you do not over heat. Is that sitting still in traffic as well as moving?
Johnny Dart. On post #90 if you go back and read you will see I plan on trying a mechanical fan if there is clearance. Also this car never had a 7 blade fan, the stock one was a 4 blade. Also my timing is at 14/32 as stated in the 1st post so you can be pretty sure that's not the issue.
As for people trying things that aren't factory that's part of the fun of a build. Yes sometimes we may become frustrated and chase our tail but most times we figure it out. I'm not a mopar purist and will never be. I "want" to be able to use electric fans. I personally think they look much better and are much safer plus they dont rob HP. Just my preference.
I dont want the simple things otherwise it would still be a 273 2 bbl.
I've gotten a bunch of really good information from this thread and I'm trying to test not just guess as I work to solving my issue. I also want to document everything as I go so others can see my path to correction and the methods i used.
Thanks for all the help so far, I'm hoping this week I get some time to try the 4 blade fan. If the car then runs cool I will look for another way to make electric fans work.
Thanks Rod
Click to expand...


How much HP does a mechanical fan Rob?
 
rod7515 said:
J par, you posted that once you removed your shroud you do not over heat. Is that sitting still in traffic as well as moving?
Johnny Dart. On post #90 if you go back and read you will see I plan on trying a mechanical fan if there is clearance. Also this car never had a 7 blade fan, the stock one was a 4 blade. Also my timing is at 14/32 as stated in the 1st post so you can be pretty sure that's not the issue.
As for people trying things that aren't factory that's part of the fun of a build. Yes sometimes we may become frustrated and chase our tail but most times we figure it out. I'm not a mopar purist and will never be. I "want" to be able to use electric fans. I personally think they look much better and are much safer plus they dont rob HP. Just my preference.
I dont want the simple things otherwise it would still be a 273 2 bbl.
I've gotten a bunch of really good information from this thread and I'm trying to test not just guess as I work to solving my issue. I also want to document everything as I go so others can see my path to correction and the methods i used.
Thanks for all the help so far, I'm hoping this week I get some time to try the 4 blade fan. If the car then runs cool I will look for another way to make electric fans work.
Thanks Rod
Click to expand...
I mean we both don't have to be a mad scientist to know that we're not getting robbed of some kind of crazy amount of horsepower. What it boils down to is just like you said we can make things work just like we see on any other car. Some people want to go on how these cars were designed for a mechanical fan and I say of course they were! No s*** Sherlock. What it boils down to is it's simple heat transfer..
Larger than stock capacity and flowing radiator, and a relatively High CFM and amp draw..
 
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IMG_20190511_172614.jpg
today it stayed cool on the first ten mile drive to a car show physically without the fans it stayed at 170 to 180. On the way back home it was in the low 80s and was up to about 190-195 maybe, but that was a lot more stop and go also..
I think I just need to stop playing with these two small fans and get one big huge one and be done with it. I'll never be happy unless I can pull that thing down to 170 at any time.
 
FWIW I just thought I’d post some info regarding a dual electric fan combo that is used to good effect by a number of Mopar owners here in Australia when running a modified engine and aluminum radiator. These are an OE Fan package from a Ford Falcon AU 5.0l with a cfm rating of about 3500 cfm and come packaged with an integrated shroud. With the right radiator they really do perform a good job in keeping an engine cool when idling in very hot conditions (>100 degrees F) The photos below are with them mounted on a locally fabricated radiator using a 2 row Griffin core in a local A Body Chrysler.
I’ve included an eBay link to give you some idea of pricing as well
New Thermo Fan Assembly fits Tickford TS50 AU 5.6L Petrol Synergy 2001 - 2002 | eBay

47E05501-EA94-4289-82E9-E7D0A27E24EE.jpeg


B619AE06-E726-4132-938B-FD4E4B430AF8.jpeg
 
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Cal Tonsley said:
FWIW I just thought I’d post some info regarding a dual electric fan combo that is used to good effect by a number of Mopar owners here in Australia when running a modified engine and aluminum radiator. These are an OE Fan package from a Ford Falcon AU 5.0l which have a cfm rating of about 3500 cfm which are packaged with an integrated shroud. With the right radiator they really do perform a good job in keeping an engine cool when idling in very hot conditions (>100 degrees F) The photos below are with them mounted on a locally fabricated radiator using a 2 row Griffin core in a local A Body Chrysler.
I’ve included an eBay link to give you some idea of pricing as well
New Thermo Fan Assembly fits Tickford TS50 AU 5.6L Petrol Synergy 2001 - 2002 | eBay

View attachment 1715333964

View attachment 1715333965
Click to expand...
the ones I posted I got from a member here that said they came off of the 440 on a motorhome LOL I don't have the CFM rating, but they do have basically a shroud at the end of the tips of the fan it's encapsulated itself..
I've been thinking about a big fat Pusher up front just for the extra, (which of course leads me to the blocking wind argument), but then again sometimes I think about one big fat one behind it...
 
rod7515 said:
J par, you posted that once you removed your shroud you do not over heat. Is that sitting still in traffic as well as moving?
Johnny Dart. On post #90 if you go back and read you will see I plan on trying a mechanical fan if there is clearance. Also this car never had a 7 blade fan, the stock one was a 4 blade. Also my timing is at 14/32 as stated in the 1st post so you can be pretty sure that's not the issue.
As for people trying things that aren't factory that's part of the fun of a build. Yes sometimes we may become frustrated and chase our tail but most times we figure it out. I'm not a mopar purist and will never be. I "want" to be able to use electric fans. I personally think they look much better and are much safer plus they dont rob HP. Just my preference.
I dont want the simple things otherwise it would still be a 273 2 bbl.
I've gotten a bunch of really good information from this thread and I'm trying to test not just guess as I work to solving my issue. I also want to document everything as I go so others can see my path to correction and the methods i used.
Thanks for all the help so far, I'm hoping this week I get some time to try the 4 blade fan. If the car then runs cool I will look for another way to make electric fans work.
Thanks Rod
Click to expand...
I'm going to be trying a couple things this summer like I said. What I have is working so far, but not as good as I would like...
 
Cal Tonsley said:
FWIW I just thought I’d post some info regarding a dual electric fan combo that is used to good effect by a number of Mopar owners here in Australia when running a modified engine and aluminum radiator. These are an OE Fan package from a Ford Falcon AU 5.0l with a cfm rating of about 3500 cfm and come packaged with an integrated shroud. With the right radiator they really do perform a good job in keeping an engine cool when idling in very hot conditions (>100 degrees F) The photos below are with them mounted on a locally fabricated radiator using a 2 row Griffin core in a local A Body Chrysler.
I’ve included an eBay link to give you some idea of pricing as well
New Thermo Fan Assembly fits Tickford TS50 AU 5.6L Petrol Synergy 2001 - 2002 | eBay

View attachment 1715333964

View attachment 1715333965
Click to expand...

That looks very high quality. The problem with most people here when they say "I'm putting on an electric fan(s) is they get the cheapest POS they can find and or they build some ridiculous air blocking shroud or both. I've preached it till I'm blue in the face. If you don't move "around" 4000 CFM you're not going to cool a hot rod engine idling. Ain't happenin. Yet time and again people try and reinvent the wheel and fail miserably. YOU have it figured out.

That's no surprise. I've said all along not to mess with Aussies. Yall take yalls cars real seriously.
 
A great read.
Lots of minds working together.
All banging away narrowing down every possibility.
A couple things. The chemical test proved positive for combustion gases. Not necessarily an issue as it will detect a minute amount of gases.
Pressure test, sure. It holds pressure.
I see it has a heater,and hoses connected. Is heater core flowing correctly? Hasnt been mentioned.
A dead sure way to check for leakage is an airlift.
It will pull air in under vacuum better than water will push out under a pressure test.

Personally, if it doesent boil over, would quit poking at it..
New engine install in a corvette had me panicking until i discovered fans dont come on until 230 degrees. Engineered that way from factory.

Engine running hot? Fans running? Place hand in a safe area downwind of cooling fans,
If heat is being carried out by air moving it will feel like a blast of hot air from your heater ducts.

Not all water pumps are that efficient either. A little too much clearance between vanes and housing and there goes your flow.

I come from a place where heat issues are a lack of heat, working towards a hotter running engine to improve comfort level in the dead of winter.
Running a 205 thermostat in summer isnt a great idea,as it will really push the limit of a pressurized system.
 
j par said:
View attachment 1715333948 today it stayed cool on the first ten mile drive to a car show physically without the fans it stayed at 170 to 180. On the way back home it was in the low 80s and was up to about 190-195 maybe, but that was a lot more stop and go also..
I think I just need to stop playing with these two small fans and get one big huge one and be done with it. I'll never be happy unless I can pull that thing down to 170 at any time.
Click to expand...

Sounds too cool , 190 is about perfect, mine wont even run right ill its been 190 for a bit .
I experimented w/ a whole bunch of elec fans , a couple of 10,000 rpm flex fans , and a short ( 2 5/8" tall" clutch fan. I only run a 17" fan , and had to go back to a mech. belt driven fan , hi flow water pump , and a stant or robertshaw thermostat-----.
 
Garrett Ellison said:
Those fans are probably pulling more air around the gaps between the shroud and radiator and the bypass holes than they are through the radiator. As otherwise noted, the fans aren't up to task, either. I would realistically think that you are looking at something like this, Zirgo Ultra High Performance Electric Fans ZIRZFU16S , and then making a shroud that seals completely to the radiator and fits the fan tightly. One common recommendation I have seen from members here that have a whole lot more experience than me in going with electric cooling fans is to use an electronic fan controller like the Dakota Digital units. These units control the fan speed to maintain a preset temperature. As you have suspected, one potential trouble area is with the J heads. Some of the J head chambers are really detonation prone, and there doesn't seem to be any specific obvious cause other than factory casting tolerance stack up causing improperly shaped and sized chambers leading to detonation.
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I would say that it's more like open Chambers or more detonation prone than a closed chamber, but then again there are better open chamber configurations then others for instance where the plug is located/where it's pointing..toward the exh valve hopefully. Sbc is closed, but the plug is miles away and nose towards nothing...so they tend to ping easier than other production closed chambers.
 
Very true, the Small Block Chrysler 340/360 style open chambers can be especially prone to detonation and overheating problems.
 
Moparofficial, I appreciate the recommendation in trying to solve the over heating problem I have, however as I have stated many times in this thread I have only 2.5" of clearance between the pump and radiator. You are recommending a fan that is 4.5" thick (according to the summit specs sheet). It just wont fit.
The reason I went with 2 smaller fans is because I couldnt find a fan that would fit in between the pump and radiator. Its the same with the fan set that a link was posted for an ebay item in Australia. Very nice looking unit and Id love to use something like that however the 2 fans are to close to the center and wont fit.
Believe me when I say I wish I could use one larger electric fan.
Its the reason I had to try to make my own shroud. I didnt like my shroud, however I didnt have much choice on how to make it.
And my fans that I bought were not cheap junk and they move 2300 CFM each. Thats 4600 cfm! But the problem I believe is that they pull in from to small of an area. I need that much drawn thru the whole radiator.
The radiator I bought came with a really nice electric fan and shroud. Nice looking quality but i couldnt fit it between the pump and radiator.
I originally didnt think a mechanical fan would fit either and i didnt try one but after some suggestions on trying it I looked and I think I might actually be able to use one so thats going to be my next change.
Thanks
Rod
 
Garrett Ellison said:
Very true, the Small Block Chrysler 340/360 style open chambers can be especially prone to detonation and overheating problems.
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You have to try hard or theorize in blunder to have overheating issues.
The combination, that's what promotes detonation in any build.
You can make anything cack cack if you running inappropriate gear wrong timing and or curve ... too high dynamic..and definitely a poor cooling system will do it.

In my experience, 'with 91 octane and open chamber' about 165 psi is the max near 'sea level' without quench...160psi and less is as safe as can be....On the other end of the spectrum 'with tight quench' ..about 185-190 psi... but its ragged edge. That's based on my own experience and not the end all... but it will keep you out of trouble hopefully.
 
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As I scan through Summit and some of those other places for a bigger fan for myself instead of the two little ones I do see I only have about 3 in between my radiator and my water pump pulley. Now I'm thinking about a pusher...
 
J par,
If your going to go to a push fan maybe you want to keep your 2 smaller pull fans. It's a thought that I have considered. I would need to move my trans cooler before I could go to a large pusher on outside of radiator. Just a thought! Let me know if you go that way.
Rod
 
rod7515 said:
J par,
If your going to go to a push fan maybe you want to keep your 2 smaller pull fans. It's a thought that I have considered. I would need to move my trans cooler before I could go to a large pusher on outside of radiator. Just a thought! Let me know if you go that way.
Rod
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Yes if I put it out front I would leave the ones behind as well. My alternator really doesn't run anything else besides the ignition and the fuel pump. Maybe a few little gauge lights inside but that's about it. I probably only have less than 10 amps of draw without the fans. I just again wanted to come all the way down and quickly.
And by the way real men don't have transmission coolers:poke:...
 
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