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18 3/4 radiator upgrade?


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8:36 AM
Sep 30, 2020
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Is there an option to upgrade from the 18 3/4 radiator without changing the radiator support? I've got the front end of the car off - perhaps it is easiest and bestest to cut the support for the tiny radiator out and swap in one for a bigger radiator. I'm only beginning to learn about this stuff - I'm surprised there are three (that I know of) different radiator supports (also different firewalls for a/c/no a/c cars). Seems like it would have been cheaper to keep it "universal" on the car side and make accommodations on the radiator side. But that's not what Chrysler did.

I'm currently thinking of putting a stroker kit in the 318, which could end up producing as much as 600hp. Not sure how streetable that would be, but, 600 hp is what I'm considering as the maximum I want in this car. The more I watch guys fishtailing into a wreck after Cars and Coffee though, the more I think of bringing that max horsepower number down!
are you asking to go from a 22 inch to a 26 inch radiator ? A member here makes brackets to do that. But some BB cars had a 22 inch radiator.
Glen Ray radiator sells the brackets needed to put a 26 inch radiator in place of a 22 inch.
And for those who aren't aware Mopar did use an 18.5" radiator but it bolts to the same radiator support as the 22" radiator...
I'm the unaware guy, it's a relief to know I can use either a 22" or 26" radiator with the support I have. And also to be able to use the 26" radiator with the 22" support if necessary. I don't mind an easy win every now and then.
Any idea how much power?
About 450 HP. It's a mild build a bit above stock. I live in the desert, and during the summer, it got warm sitting but never overheated. Call Cool Craft and see what they say. I would go with a 26-inch if you can fit it. Bigger is probably better when it comes to radiators and high HP big blocks.
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Mine is going to be a small block, hopefully in the same horsepower range. 26" sounds good for "future proofing," I wonder how much cooling capacity the 26" radiator loses when partially blocked by the 22" support?
Bob at Glen Ray radiator said there's not much cooling loss from having some of the radiator blocked. The radiator will do its job just fine. I did the same thing, and saw a drop in temperature. And I've also got a fan shroud, and 18 inch 7 blade flex fan.
I wonder what the difference in weight is between 18, 22, and 26?
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