Griffin radiator and twin fans still running at 190-200?

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I only asked the question because I am smart enough to know that anybody on here with answers has at one time learned them from someone else, correct? I did say in my post that I have yet to take the car on the road. So thanks for all the good answers and no thanks to the answers that have no input relative to the question.
 
I only asked the question because I am smart enough to know that anybody on here with answers has at one time learned them from someone else, correct? I did say in my post that I have yet to take the car on the road. So thanks for all the good answers and no thanks to the answers that have no input relative to the question.
It sounds like the fans, shroud, and radiator all came together? Wasn't this supposed to be rated for a certain amount of cooling as a package? I think it'll be interesting to see what happens when you do drive it. If the temperature does go down and it is the CFM of the fans?
I'm interested in this again as I'm having the same exact issues with a pretty hot 410 Stroker. In comparison I have a stock radiator with my own homemade aluminum shroud and to 12in fans that I bought from remember here that were supposedly in a motorhome with a 440. I can tell you one 20 amp fuse will not support the two of them wired together. It needs a 30 amp fuse or it will blow. At this point I'm taking into consideration just riveting a new Shield over top and cutting a new hole for one big huge fan and if that will work better, which it seems like it might.
IMG_20180402_180807.jpg

I have 65 amps total and I'm not sure if I have enough to support another Pusher fan or something?
Please excuse yellow rose he can't help himself derailing threads. You can see I tried to ward him off with the word snowmobile! that's usually like Kryptonite to him and keeps him away.
 
It sounds like the fans, shroud, and radiator all came together? Wasn't this supposed to be rated for a certain amount of cooling as a package? I think it'll be interesting to see what happens when you do drive it. If the temperature does go down and it is the CFM of the fans?
I'm interested in this again as I'm having the same exact issues with a pretty hot 410 Stroker. In comparison I have a stock radiator with my own homemade aluminum shroud and to 12in fans that I bought from remember here that were supposedly in a motorhome with a 440. I can tell you one 20 amp fuse will not support the two of them wired together. It needs a 30 amp fuse or it will blow. At this point I'm taking into consideration just riveting a new Shield over top and cutting a new hole for one big huge fan and if that will work better, which it seems like it might.
View attachment 1715175667
I have 65 amps total and I'm not sure if I have enough to support another Pusher fan or something?
Please excuse yellow rose he can't help himself derailing threads. You can see I tried to ward him off with the word snowmobile! that's usually like Kryptonite to him and keeps him away.
Yes, I bought it as a package from Griffin radiator. They told me it would run real nice as built. $1200.00 was a lot of money but I like to keep my money in American labor when I can. And regarding CFM flow of a fan, you have to be able to also factor in the tightness of the louvers and radiator fins. CFM means nothing without determining what you are pulling or pushing through?? Same as a blocked filter on an A/C unit. All the fan in the world is no good if the filter is blocked, right?? I will continue to post my findings here. The CFM rating of these two fans is suppose to be plenty for the radiator and shroud they designed. I fused mine on two separate circuits with a 15amp fuse for each. No issues there.
 
I'm a firm believer that car knowledge is car knowledge and if it could be passed along and be helpful it's all good. I thought I seen once or twice, I don't think it was you maybe another vendor where it starts to become a commercial for their products when they post and that can get a little sticky. My-2 and again thanks for your experience..
Could have been me. I guess it all depends on what you think a commercial should be like. ;) Yes we are a sponsor. Yes we sell radiators but I am very conscious of my participation. If I think we have a good solution, I'll usually PM. If I think I can add something to the knowledge base, I participate. I think this topic is a good example. There's nothing we can help the topic starter with. He made a very high quality choice but he still had questions revolving around his combination.
 
It sounds like the fans, shroud, and radiator all came together? Wasn't this supposed to be rated for a certain amount of cooling as a package? I think it'll be interesting to see what happens when you do drive it. If the temperature does go down and it is the CFM of the fans?
I'm interested in this again as I'm having the same exact issues with a pretty hot 410 Stroker. In comparison I have a stock radiator with my own homemade aluminum shroud and to 12in fans that I bought from remember here that were supposedly in a motorhome with a 440. I can tell you one 20 amp fuse will not support the two of them wired together. It needs a 30 amp fuse or it will blow. At this point I'm taking into consideration just riveting a new Shield over top and cutting a new hole for one big huge fan and if that will work better, which it seems like it might.
View attachment 1715175667
I have 65 amps total and I'm not sure if I have enough to support another Pusher fan or something?
Please excuse yellow rose he can't help himself derailing threads. You can see I tried to ward him off with the word snowmobile! that's usually like Kryptonite to him and keeps him away.


I don't think 65 amps is near enough. Just opinion. And when the fans draw down the power the ignition gets weaker, the exhaust temp goes up and engine temp creeps up. It's a vicious circle.
 
i was contributing because the topic starter was 'concerned' with the temps he was running. Several of you gave good advice about making him feel comfortable with the safety of 210-220 temps. While it may be unnecessary to run at 190 all the time, there are advantages. Many owners are not comfortable when that heat starts pushing into the interior. It's uncomfortable and there is also a mental aspect of the car being close to overheating. I happen to be one of those people. So I gave him a couple of ideas based on his situation.

As far as my recommendation, while you are absolutely correct that fan CFM can range greatly, if you compare apples to apples, a 16" Spal fan is going to outperform 2 10" Spal fans of the same line. That was my point. Our topic starter's temps are rising 15 degrees when at idle. The rise in temp at idle is directly related to air flow. Hence my comments on fans.

We're all here on these forums to contribute information that can help increase our collective knowledge about any particular topic with the assumption that future viewers may benefit as well. I'm fairly new on the forums but I'm not new to dealing with cooling issues. I think we have some pretty good knowledge that can help members here and there. I hope you long time contributors are open to that.

I’ve got no issues with vendors chiming in, good information is good information.

But he nothing he’s describing suggests he needs new fans. And if he did need new fans, using fan diameter instead of rated cfm to choose them is folly. Sure, cfm ratings can vary by manufacturer, it depends on how they’re actually doing their testing. But it’s a far better measure of fan performance than just diameter.

Engine temperature isn’t what you feel coming through the firewall either. That’s engine compartment temperature, and that’s from the exhaust manifolds or headers. Running at 190 or 200 vs 180 isn’t going to change that one bit.

Personally, I’m not big on SPAL fans. They’re overpriced for what they are and what they do. Cheap aftermarket fans aren’t usually good, that’s true. But you don’t need to spend several hundred dollars to get a good electric fan. The reproduction Ford Contour fan system I use is like $130 from Dorman, and it will even outperform the black magic fan @RustyRatRod likes. Although at 4,000 cfm I’m sure that fan works just fine, most of the time mine are running on low speed at ~3,000 cfm.

It sounds like the fans, shroud, and radiator all came together? Wasn't this supposed to be rated for a certain amount of cooling as a package? I think it'll be interesting to see what happens when you do drive it. If the temperature does go down and it is the CFM of the fans?
I'm interested in this again as I'm having the same exact issues with a pretty hot 410 Stroker. In comparison I have a stock radiator with my own homemade aluminum shroud and to 12in fans that I bought from remember here that were supposedly in a motorhome with a 440. I can tell you one 20 amp fuse will not support the two of them wired together. It needs a 30 amp fuse or it will blow. At this point I'm taking into consideration just riveting a new Shield over top and cutting a new hole for one big huge fan and if that will work better, which it seems like it might.
View attachment 1715175667
I have 65 amps total and I'm not sure if I have enough to support another Pusher fan or something?
Please excuse yellow rose he can't help himself derailing threads. You can see I tried to ward him off with the word snowmobile! that's usually like Kryptonite to him and keeps him away.

A single fan won’t necessarily work better. Again, it’s down to the shroud and fan cfm. Two fans have some advantages though, the fan motors are offset so sometimes you get more clearance to the pulleys because the fan motor isn’t right inline with the pulley. And if a motor craps out you lose one fan instead of both of them (assuming they’re wired correctly). Not a terrible idea with electric fans, I can get home with one fan running on high speed.

Yes, I bought it as a package from Griffin radiator. They told me it would run real nice as built. $1200.00 was a lot of money but I like to keep my money in American labor when I can. And regarding CFM flow of a fan, you have to be able to also factor in the tightness of the louvers and radiator fins. CFM means nothing without determining what you are pulling or pushing through?? Same as a blocked filter on an A/C unit. All the fan in the world is no good if the filter is blocked, right?? I will continue to post my findings here. The CFM rating of these two fans is suppose to be plenty for the radiator and shroud they designed. I fused mine on two separate circuits with a 15amp fuse for each. No issues there.

Cfm doesn’t “mean nothing”. Sure, the rated cfm may be different from the actual cfm, especially if the fan is a standalone deal that you’ve installed with some random shroud. But if you start with a 600 cfm fan you’re not going to make it pull 5000 cfm. That’s why I like electric fans that are built into a shroud and designed as a whole unit, not aftermarket stuff that’s rated as a stand-alone. Who knows what your actual flow is. With the fans as part of a whole system, with the system rated for 3000 cfm and 5000 cfm, I know there’s a good chance my actual cfm will be close to the rated cfm as long as I’m not doing anything to significantly restrict the airflow through radiator.
 
I am not a pro by any means....But it seems like the majic CFM number to keep a vehicle COOL all the time ... i don t care if you use a combo of elec and mechanical or just electric or mechanical is 3000-3500 cfm ....as long as all other cooling system components are working correctly....so as stated earlier....if you get a 7 blade mechanical fan and a pusher capable 1000-1200 cfm with a shroud ( if the fan distance to radiator is 4 inches or more ) on engine side , you should be ok .
 
It sounds like the fans, shroud, and radiator all came together? Wasn't this supposed to be rated for a certain amount of cooling as a package? I think it'll be interesting to see what happens when you do drive it. If the temperature does go down and it is the CFM of the fans?
I'm interested in this again as I'm having the same exact issues with a pretty hot 410 Stroker. In comparison I have a stock radiator with my own homemade aluminum shroud and to 12in fans that I bought from remember here that were supposedly in a motorhome with a 440. I can tell you one 20 amp fuse will not support the two of them wired together. It needs a 30 amp fuse or it will blow. At this point I'm taking into consideration just riveting a new Shield over top and cutting a new hole for one big huge fan and if that will work better, which it seems like it might.
View attachment 1715175667
I have 65 amps total and I'm not sure if I have enough to support another Pusher fan or something?
Please excuse yellow rose he can't help himself derailing threads. You can see I tried to ward him off with the word snowmobile! that's usually like Kryptonite to him and keeps him away.
^^^^^^^^
^^^^^^^^ snowmobile,

I was wondering about that, really stumped me ! but that aint hard.
 
I don't think 65 amps is near enough. Just opinion. And when the fans draw down the power the ignition gets weaker, the exhaust temp goes up and engine temp creeps up. It's a vicious circle.
Can you show your math? This may clear up your "opinion"?
 
^^^^^^^^
^^^^^^^^ snowmobile,

I was wondering about that, really stumped me ! but that aint hard.
My two 10" fans have what Griffin calls a true CFM rating of 898 per fan. So we are at about 1800CFM and the radiator has two 1" cooling tubes. The shroud is custom fit to the radiator with 8 rubber flaps which are forced open as the car gains speed. As stated earlier. I have not driven the car yet. Just talking about idling right now. I seem to be hearing that 210 is not really all that hot for this build? That is good news, and I will post what happens down the road when I take her up the highway.
 
My two 10" fans have what Griffin calls a true CFM rating of 898 per fan. So we are at about 1800CFM and the radiator has two 1" cooling tubes. The shroud is custom fit to the radiator with 8 rubber flaps which are forced open as the car gains speed. As stated earlier. I have not driven the car yet. Just talking about idling right now. I seem to be hearing that 210 is not really all that hot for this build? That is good news, and I will post what happens down the road when I take her up the highway.
Honestly for "$1200"! Something almost has to be wrong. At that kind of $$$$ I would like to think that the temperature would hold rock solid at whatever temperature thermostat you put it in there.
Especially for me if I was able to do similar or slightly better with a stock radiator a homemade shroud and some $40 used fans.
My mind works mostly mathematically is the way I figure it and this don't add up.
 
Honestly for "$1200"! Something almost has to be wrong. At that kind of $$$$ I would like to think that the temperature would hold rock solid at whatever temperature thermostat you put it in there.
Especially for me if I was able to do similar or slightly better with a stock radiator a homemade shroud and some $40 used fans.
My mind works mostly mathematically is the way I figure it and this don't add up.
Why do you think I supplied this Post to Abodies?? There is another issue that I have not checked yet. When installing this whole thing, I failed to re-install a grounding wire from the front light harness and I also noticed that the terminal end of my black negative battery cable which is grounded to the aluminum head had a real loose crimp and pulled out with a tug. I know grounds play major issues with Mopars. I am wondering if the grounds are playing with the sending units and not allowing the fans to go on at the 185 temp?? I will get them fixed and repost here to keep all interested parties informed to maybe help someone else.
 
My two 10" fans have what Griffin calls a true CFM rating of 898 per fan. So we are at about 1800CFM and the radiator has two 1" cooling tubes. The shroud is custom fit to the radiator with 8 rubber flaps which are forced open as the car gains speed. As stated earlier. I have not driven the car yet. Just talking about idling right now. I seem to be hearing that 210 is not really all that hot for this build? That is good news, and I will post what happens down the road when I take her up the highway.

I don't know what they mean by "true cfm". That's not scientific jargon, that's sales and marketing. I know that there are different testing methods to come up with a rated cfm, so you can't necessarily assume one manufacturer's rating is the same as another. But 1,800 cfm seems very low. It's like comparing different dyno numbers or flow bench ratings. What one dyno says and what another one says may not mean the exact same thing. But, they should be in the same ballpark. 1,800 cfm isn't in the same ballpark. That's half.

But yes, I wouldn't be too stressed out about a car that's holding and maintaining 210 at idle. It is a little high considering I don't think you're dealing with ambient temperatures that are all that hot yet, but with a new engine and a car that hasn't been on the road yet I wouldn't be buying new fans just yet. It's worth watching, but I think you have more tuning to do.

Why do you think I supplied this Post to Abodies?? There is another issue that I have not checked yet. When installing this whole thing, I failed to re-install a grounding wire from the front light harness and I also noticed that the terminal end of my black negative battery cable which is grounded to the aluminum head had a real loose crimp and pulled out with a tug. I know grounds play major issues with Mopars. I am wondering if the grounds are playing with the sending units and not allowing the fans to go on at the 185 temp?? I will get them fixed and repost here to keep all interested parties informed to maybe help someone else.

Yes, the grounds are very important. I mentioned this earlier I think too, if the fans aren't able to pull the amperage they need, you aren't going to get that rated cfm. And if you have poor grounds, you won't supply the needed voltage. It could also mess with the sending units, but I think you need to confirm your temperatures with an IR or other methods to make sure the discrepancy isn't the gauges. Could be the fans are operating fine and the temp gauge you're looking at is off.
 
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I don't know what they mean by "true cfm". That's not scientific jargon, that's sales and marketing. I know that there are different testing methods to come up with a rated cfm, so you can't necessarily assume one manufacturer's rating is the same as another. But 1,800 cfm seems very low. It's like comparing different dyno numbers or flow bench ratings. What one dyno says and what another one says may not mean the exact same thing. But, they should be in the same ballpark. 1,800 cfm isn't in the same ballpark. That's half.

But yes, I wouldn't be too stressed out about a car that's holding and maintaining 210 at idle. It is a little high considering I don't think you're dealing with ambient temperatures that are all that hot yet, but with a new engine and a car that hasn't been on the road yet I wouldn't be buying new fans just yet. It's worth watching, but I think you have more tuning to do.



Yes, the grounds are very important. I mentioned this earlier I think too, if the fans aren't able to pull the amperage they need, you aren't going to get that rated cfm. And if you have poor grounds, you won't supply the needed voltage. It could also mess with the sending units, but I think you need to confirm your temperatures with an IR or other methods to make sure the discrepancy isn't the gauges. Could be the fans are operating fine and the temp gauge you're looking at is off.
 
I spoke with Griffin radiator today. Customer service told me that they recommend installing the 185 degree temperature sending unit into the drain **** post on the lower tank of the radiator. She said the install on top the intake manifold may be creating adverse higher temperatures which will play games with the signal being sent to the relays to turn the fans on at the right temp. Also my negative battery cable came lose from the terminal end and she said that may also cause the sending unit to be sending a delayed signal to the relays which will cause the fans to come on at a higher temp. She also told me that they work very closely with Spal when designing these exact fit combo units and it should cool my car very nicely. So I am going to fix the grounds first and take her out for a ride. If I still have temp creep, I will install the sending unit in the drain **** as they recommend. Sounds plausible to me, so I will give it a try and report back here as soon as I get her done.
 
I spoke with Griffin radiator today. Customer service told me that they recommend installing the 185 degree temperature sending unit into the drain **** post on the lower tank of the radiator. She said the install on top the intake manifold may be creating adverse higher temperatures which will play games with the signal being sent to the relays to turn the fans on at the right temp. Also my negative battery cable came lose from the terminal end and she said that may also cause the sending unit to be sending a delayed signal to the relays which will cause the fans to come on at a higher temp. She also told me that they work very closely with Spal when designing these exact fit combo units and it should cool my car very nicely. So I am going to fix the grounds first and take her out for a ride. If I still have temp creep, I will install the sending unit in the drain **** as they recommend. Sounds plausible to me, so I will give it a try and report back here as soon as I get her done.

The grounds are definitely important, and can effect both the sending unit and the fan motors themselves.

As for the “185 degree sending unit”, that’s the fan switch you’re using. Are you sure you have the temperature range on that switch for triggering the fans right? Because turning the fans on at 200 and off at 185 is pretty common for a non-adjustable switch. On at 185 and off at 165 isn’t a common range.

As for moving the switch, it should function just fine in the top of the intake. Moving it to the drain petcock would mean putting it after the water has been cooled by the radiator, so the fans would come on at a higher engine coolant temperature because they’re seeing water that’s been cooled instead of the water coming from the engine before it goes through the radiator. So that doesn’t make any sense at all, because you already think the fans are coming on too late. Putting them in the cooler water after the radiator pass will only delay them further.

***edit***

Ok, maybe scratch that last part. I was thinking of a standard downflow radiator, and I think your Griffin is a cross-flow. So, whether or not the water has been cooled depends on which tank the drain petcock is in. It could be on the engine side, which would be before the radiator pass. Although in that case, moving the switch there shouldn’t change much.
 
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The grounds are definitely important, and can effect both the sending unit and the fan motors themselves.

As for the “185 degree sending unit”, that’s the fan switch you’re using. Are you sure you have the temperature range on that switch for triggering the fans right? Because turning the fans on at 200 and off at 185 is pretty common for a non-adjustable switch. On at 185 and off at 165 isn’t a common range.

As for moving the switch, it should function just fine in the top of the intake. Moving it to the drain petcock would mean putting it after the water has been cooled by the radiator, so the fans would come on at a higher engine coolant temperature because they’re seeing water that’s been cooled instead of the water coming from the engine before it goes through the radiator. So that doesn’t make any sense at all, because you already think the fans are coming on too late. Putting them in the cooler water after the radiator pass will only delay them further.

***edit***

Ok, maybe scratch that last part. I was thinking of a standard downflow radiator, and I think your Griffin is a cross-flow. So, whether or not the water has been cooled depends on which tank the drain petcock is in. It could be on the engine side, which would be before the radiator pass. Although in that case, moving the switch there shouldn’t change much.
OK. All that sounds like things I need to recheck. Especially the 185 degree off and 200 on. I don't know where I read the 165 off but I will recheck that. I kind of thought the 165 off seemed rather cool considering most normal cars operate at about 180-190. So I will also check that and let you guys know over the weekend. Thanks for that info.
 
Can you show your math? This may clear up your "opinion"?


You have to add up all the amps used by the system. Lights, heater, fuel pump, fans, ignition and any other electrical components. Then you add a safety margin and pick an alternator.

65 amps is pretty puny by today's standards.
 
You have to add up all the amps used by the system. Lights, heater, fuel pump, fans, ignition and any other electrical components. Then you add a safety margin and pick an alternator.

65 amps is pretty puny by today's standards.
Don't drive this car at nights and heater is not used as car is stored in the winter. Radio is solid state and a/c compressor is a new sanden compressor which hardly draws any big amps? Car has a high flow mechanical fuel pump? So I do not think that alternator amperage draw is the problem.
 
Don't drive this car at nights and heater is not used as car is stored in the winter. Radio is solid state and a/c compressor is a new sanden compressor which hardly draws any big amps? Car has a high flow mechanical fuel pump? So I do not think that alternator amperage draw is the problem.

Yeah but what do the fans pull? My fans will pull ~35 amps on start up, and only drop into the mid-twenties on the lower speed. That doesn't leave much. Also consider that your alternator is not capable of producing 65 amps at any given time. At idle speeds it's not capable of putting out that much. I forget exactly how they're rated, but I know for a fact that the rated output is not what it will put out at idle or lower speeds.

I run a 100 amp alternator on my car.
 
Yeah but what do the fans pull? My fans will pull ~35 amps on start up, and only drop into the mid-twenties on the lower speed. That doesn't leave much. Also consider that your alternator is not capable of producing 65 amps at any given time. At idle speeds it's not capable of putting out that much. I forget exactly how they're rated, but I know for a fact that the rated output is not what it will put out at idle or lower speeds.

I run a 100 amp alternator on my car.
I think mine is 65. Chrome alternator. If I have issues I will just trade it up for a 100 amp version. I will keep posting here until I get it right and let you guys know what I find. I fixed the battery negative cable so tomorrow I am going to go for a short cruise and get a new inspection sticker. So that will be the maiden voyage with the new radiator and spal fans. Hoping it will surprise me. Spal told me that the sending unit I have is 185 degrees on and 165 degrees off. They have a higher one as well but they told me it is better to have them running constantly while the car is running. So I guess it will never see the 165...
 
I think mine is 65. Chrome alternator. If I have issues I will just trade it up for a 100 amp version. I will keep posting here until I get it right and let you guys know what I find. I fixed the battery negative cable so tomorrow I am going to go for a short cruise and get a new inspection sticker. So that will be the maiden voyage with the new radiator and spal fans. Hoping it will surprise me. Spal told me that the sending unit I have is 185 degrees on and 165 degrees off. They have a higher one as well but they told me it is better to have them running constantly while the car is running. So I guess it will never see the 165...

The information you're getting from SPAL is pretty interesting, and not in a good way. It's not better to have the fans running all the time. They should cycle on and off as needed, and they shouldn't be on at all when you're maintaining a constant speed that's much faster than 30 mph. The radiator should be able to handle that without the fans in most conditions.

To me, if the fans are running all the time it either means the radiator is too small or the fans don't put out enough CFM. You should be able to have the fans kick on at 200, cool the car down to 185, then shut off. If you're cruising, they should be able to stay off and the radiator do the work. The whole point of the electric fans is that they aren't running all the time, you're not wasting power driving a fan that you don't need. You should be able to set them to maintain the operating temperature you want, so the car stays in that range.
 
You have to add up all the amps used by the system. Lights, heater, fuel pump, fans, ignition and any other electrical components. Then you add a safety margin and pick an alternator.

65 amps is pretty puny by today's standards.
Fans!22
Water pump 5
Fuel pump 1
ignition 4 or .7 per 1k
O2 sensor 1?
Tac it's light and the little water- oil-voltage gages 2?
 
The information you're getting from SPAL is pretty interesting, and not in a good way. It's not better to have the fans running all the time. They should cycle on and off as needed, and they shouldn't be on at all when you're maintaining a constant speed that's much faster than 30 mph. The radiator should be able to handle that without the fans in most conditions.

To me, if the fans are running all the time it either means the radiator is too small or the fans don't put out enough CFM. You should be able to have the fans kick on at 200, cool the car down to 185, then shut off. If you're cruising, they should be able to stay off and the radiator do the work. The whole point of the electric fans is that they aren't running all the time, you're not wasting power driving a fan that you don't need. You should be able to set them to maintain the operating temperature you want, so the car stays in that range.
So, maybe I should change the sending unit to the on at 200 and off at 185. They sell that one? I have no idea why they Griffing radiator gave me the 185-165 sender with the combo kit I bought? Odd?
 
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