440 radiator size?

[mint6551]

Hey was just wondering if anyone could give me some advice on a radiator for my 1973 challenger. It was a 340 4 speed, I dropped in a 440 with an automatic and am trying to find out the radiator size I need. I think ive narrowed it down to a 22 inch wide radiator or a 26 inch wide radiator?? Thats the core width, I measured it and it seems if I go any bigger than the 22 inch wide radiator it will cover up the bolt holes to mount the radiator. Any advice would be helpful thanks!!

[Chryco Psycho]

the factory did build some 440 cars with a 22" wide rad triple core & with a high efficiency core you can get away with that using a shroud & clutch fan , you can also but the one side of the rad wall to make it correct for the 26" rad or bolt in the wider rad using the existing rad wall ut make sure you still use the shroud & clutch fan

[mint6551]

So the 22 inch radiator should work?

[Chryco Psycho]

triple core & clean yes it should , but there are a huge @ of variables , A/C ambient temp sitting in traffic , good water flow , shroud & clutch fan , etc but worth a try

[mint6551]

Thanks!

[Topcat]

Might be worth adding to help lower temps.

http://www.redlineoil.com/Products.aspx?pcid=10

[slsc98]

I am separated from my 73 w/ non-orig 440 as I type this but, I just went down to check the files I got from previous owner. Found a receipt where he paid to have the front and rear cores rebuilt but, no mention of size. Since whomever assembled the car before he bought it left the original 4-spd front bearing retainer (WRONG OD!!!  ) in it when they dropped the 440 in, I am confident they left the original 340 radiator in it, which I am (again) assuming is the 22"

Like CP says (always! ;-), make sure you install a fan shroud.  I was told over and over but, had to see it with my own experience just what an incredible increase in air flow and performance a little piece of plastic like a fan shroud can make. So much so that now, when I'm checking old cars out for possible purchase, if I don't see a fan shroud a "red flag" goes up for me and I start wondering / asking how long and hard the engine has been running without benefit of the shroud being there, etc.

(Don't know if my car has a clutch fan in it but, that'll be something for me to put on my bucket list, even though I feel sooooooo blesses over how incredibly cool my engine runs (one BIG thing less to worry about!) so, you're pretty smart IMO to be putting emphasis on this aspect of engine wear and care . . .

PS - I don't have any experience with the additive Topcat mentions but, this past summer my wife and I did add Joe Gibbs Coolant System Protectant (CSP) to our radiators and, while not very 'scientific', I swear I noticed a marked and visible difference in the already 'good behavior' of my temp gauge . . .

I have always been impressed with the 'science' and independent test results of the various Joe Gibbs / Driven Racing products (absolutely love and swear by their *non-synthetic* high zinc / pddf Hot Rod engine oils!!!) but, that said, there sure is a lot to choose from, in the way of radiator additives!:

http://www.jegs.com/c/Cooling-AC-Heating_Coolant-Coolant-Additives/10121/10002/-1

If you already have a 22" my guess is you'll be in high cotton, as long as it is truly clean inside AND you install a shroud and clutch fan.

Best o' success (and post some pics of your '73 w/ 440, please!   

Follow-up: I swung by MyMopar's Tech Manual / Reference Tools section and came across this Service Manual on Cooling Systems: http://www.mymopar.com/downloads/mtsc/251.pdf

Lotsa great info but, no mention of size rad to engine (hope I am not committing any "forum feux pax" between various forums?)

But, if you have the time and a high speed Internet connection, I am sure one of the Body / Chassis Manuals available there (or maybe also MoparTech.com) should have reference info that may assist you

[rattlesnake]

 , but if you want to do it only one time go bigger. Nothing sucks as much as putting something together and having it all pretty and clean then having to tear it down because you shaved a few dollars here and there. As chryco said the 22" is borderline if all conditions are perfect but odds are they are not so go bigger and mount the radiator in new holes if needed, its easy to do.

[mint6551]

Thanks everyone, I ended up putting a champion radiator in 26". The radiator ends up fitting perfectly with the open space on the front of the car, to me anything bigger would have been a waste because the metal would have blocked any air from going through. I appreciate all the help tho, Im just getting started on this car I have a long ways to go and probably a ton of more questions. Im more of a body guy, whose trying to learn the mechanic side as I go. Thanks!

[Chryco Psycho]