Cummins Radiator?

BrandonMag

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I've been getting the parts together for my F350 Cummins conversion... which was originally powered by a 460. I've been looking for a Ford 7.3 IDI radiator, but recently talked to someone who had done a Cummins conversion on a Chevy and had used a large radiator (apparently off a Chevy 6.2 diesel). He said the Cummins doesn't seem to make nearly as much heat as the other diesels (such as the 6.2s and IDIs), because with the big radiator he's running and a 165* thermostat, in the winter his heater doesn't get hot enough to even defrost his windows. :confused:

Has anyone here who's done a Cummins conversion used a 7.3 IDI radiator and had a lack of heat coming through the vents once the engine was warm?

If so, would it be acceptable to use the 460 radiator that came with my F350? If not, what about the stock Dodge radiator (which is about half the capacity of the Ford IDI radiator)?
 

Darrin Tosh

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I have no problems with my IDI Radiator, It is overkill for the Cummins and it never runs over 185 degrees no matter what I am doing with the truck.

My guess is that the 460 Radiator would be fine to cool the Cummins.

I just did a Cummins 4bt swap on Droopy,That was a 5.0 302 and used that radiator. Just like Big Ed, the temp has not gone over 180. No grant it, I only put 450 miles on it so far, and it is winter, but I think it is going to be fine for what I do with the truck.
 

MIDNIGHT RIDER

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I have the cavernous 1985 Ford diesel w-A/C radiator in front of my 6BT Cummins and the Cummins recommended 180* thermostat.

My gauge climbs to 180* and stays there, up hill and down, regardless of the grade or the outside temperature.

My heater will roast you out of the cab on the coldest days.

Maybe the lack of heat problem you mentioned some other guy having is mostly due to his 165* thermostat.


Regardless of radiator size, the thermostat is what governs how hot the engine gets, so long as the radiator has the capacity to prevent over-heating.

You should experience just as much heater performance with a huge radiator as with a tiny radiator.
:)
 

chvycmnslvr68

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you should use the factory ford radiator partly cuz it already mounts in the truck and that alone will save you lots of time on your conversion .. the early dodge cummins did not have enough cooling capacity .. but any ford or chevy big block or diesel radiator will provide sufficient cooling .. much better than the dodge radiator will ... and as far as the heater goes ... if your thermostat is working you should not have any problems with your heater getting hot enough .. But i can tell you from experience that if your engine is not running at temperature (180) your fuel economy will fall off dramatically and if you can find a 195 you will gain even a couple more MPG's out of it
 
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