1970 Cuda 340 -what radiator will work or is correct?

[electros]

My 1970 Cuda project is getting underway and I am gathering parts and info-  My car is an original 6 cylinder car and currently has a 318-I have a date coded 70 340 that I am going to install----------------------The existing radiator is some odd junk not Mopar but my issue is the core support opening is 22"
and I see that a correct radiator would be a 22 or 26:-will either size bolt up to a stock support with factory holes?  Seems a 26" would hang over and not get air flow- also which size is better for cooling or does this not matter since both will cool adequately -  any info helps or pictures of what you have------- thanks

[Beekeeper]

You need a 22" if that's the size of the opening. 26" is better but if the opening isn't there, no point. You could switch out the side part for the one they used in the 26" but another much easier option would be to go with a thicker three row radiator or better yet, a new aluminum one. they cool very well.

[electros]

If I did aluminum it would be stock type shape rather than squared off straight  edges-but-I would worry that a 22  would not cool as good or fast as a 26-normally I would not worry but I just don't want to have to do this twice if 22 is an issue-

[Katfish]

I put a 26" in my 22" opening, small overlap.
The extra capacity definitely cools better.

[Beekeeper]

I used a 22" Griffin in my Super Bee and it was great. Aside from being aluminum color, it looked fairly original. Check them out. They use two thin rows but the rows are very long rather than the puny original size. The result is that the radiator has much more cooling capacity. Like WAY more. They make them in different thicknesses too so if cooling is an issue, you can get the thicker one and it will still fit in the opening.

Two words of caution though, I went with the thickest one they offered and while it cooled great, it was so thick that it interfered with the fan clutch. I had to run a seven blade non clutched fan. Still worked well but kinda noisy. Next time, I'd go a bit thinner and use the clutch. Second word of caution....the Griffin did not come with tabs on the inside to mount the shroud. Kinda pissed me off to have to take a new $600 radiator to my local welder to have them fabricate and weld on tabs that Griffin should have put on. As far as Griffin was concerned, original Mopars never came with shrouds which of coarse is rediculous.

[electros]

That's another issue-do I need a fan clutch?  An what fan blade would be best as well?  I think the 318 in the car has a 7 blade of some kind that is riveted and no fan clutch-

[Beekeeper]

You don't need a fan clutch but they are nice because they save a little bit of horsepower that would normally be required to spin a fan without a clutch. They also keep fan noise down which probably isn't that big a deal.

More blades means more air. You need a good shroud so the fan is forced to pull air through the radiator at slow speeds instead of around it. Ideally, you will want the fan about halfway into the shroud opening. It should be as large in diameter as the shroud opening allows (roughly).

[Chryco Psycho]

Definatly run a clutch fan ,these are the most efficient system I use the Flex-A-Lite 18 " 6 bade in most cases
the extra capacity of a 26 " rd is often worth it for better cooling even if it wider then the opening