Cooling System Installation

I apologize for being late on this update. My better half had some health issues and caring for her kept me out of the garage for a while. However, I did find some time during the last month to get some work in the garage completed.

Keeping in mind that I want to get this car running and moving under its own power the next step was to install the cooling system. Once again, I am on a pretty strict budget on this build so no multi dollar Walker or other high end radiator will find its way into this engine compartment. (I wouldn't use a Walker POS radiator if you payed me, but that's another story.) Anyway, given that we're working with a relatively low compression 440 (9.2:1) with AC in a pretty hot area of the country, I decided to go with an aluminum radiator. When it comes to Mopars there are a few choices when it comes to aluminum radiators, and they come in 2 core, 3 core, and 4 core versions for the early 22" width and later 26" width core supports. The 1964 Dodge and Plymouth "B" bodies used the 22" width radiator and not wanting to modify my radiator support to accept the wider 26" wide radiator, (there isn't enough room anyway), I decided to stick with the stock width of 22".

This creates a problem when it comes to cooling a big block with AC. The stock radiator did not have a shroud and used a four blade fan to cool the 383 big block that was installed at the factory. This was adequate given it was a non AC car. To insure good cooling using an aluminum radiator in 22" width, I went with a 2 core unit with 1" tubes. These large 1" cooling tubes will provide more contact area for heat exchange and will cool better than either the 3 or 4 core radiators in my application. Although many may not think so based on conventional thinking, it is a fact that larger tubes cool better than small tubes not only because of the increased contact area but also because there is less restriction and more air can pass through. I did a lot of research on the subject and I'm convinced these larger 1" tubes will cool better in this application. OK, enough of that. Here is a picture of the large 1" tubes.

This is a Champion 2 core 22" width aluminum radiator that I purchased from Summit Racing. You can find these on EBay but I decided to buy from Summit because I knew it would be easier to return if there were any fitment issues. There were a couple minor issues but they were easily solved by elongating the upper mounting holes on the radiator flange. No big deal and it took about 10 minutes to do this. Here is the radiator temporarily fitted. As you can see there is just not enough room to install the 4" wider radiator.

The next project was the fan. I knew I would not be using the stock four blade fan and I also knew I wanted to use the largest one possible given the space I have available. The best fit was an 18" 6 blade fan. I could have used a clutch fan but I chose a simple six blade unit. There is no room for a large electric fan because the room between the water pump pulley and the (thicker than stock) aluminum radiator just won't allow it. Electric fans have their place, but I like mechanical fans better in a car of this vintage. Here is the one I chose. An 18" rigid race fan with steel blades in standard rotation rated to 8000 rpm. Summit part number DER-17318.

I also knew I wanted to use a shroud to increase cooling at idle and low speeds. You can find and even purchase reproduction shrouds for these cars but they are pricey and the Mopar tax is just more than I wanted to spend. A reproduction unit will run you about $140-$180 which is just too much for my budget. So I decided to build my own.

Unfortunately I neglected to take any pictures of the shroud build but I will do my best to describe it here.

With the radiator temporarily installed the fan was mounted to the water pump pulley and a measurement was taken between the leading edge of the fan and the radiator. It was about two inches which was a little too much so a one inch spacer was needed to move the fan closer to the radiator core. I just happened to have one left over from a previous build that was just under an inch so I used that one.

Next a cardboard template was constructed the same size as the radiator core and since the fan's rotation is a little above the top of the core and below the bottom of the core a couple extra pieces of cardboard were added to the top and bottom of the template. Then a marker was taped to the outside edge of one fan blade and the fan was rotated so that the marker transferred the fan's position to the cardboard template. The template was then removed and 20 gauge steel was used to make the shroud. Now, 20 gauge steel is pretty thin material but it is easy to work with and can be easily cut with metal shears. The shroud was fit, trimmed, and re-fit several times to get things aligned and sized so the fan could rotate properly without interference. Tack welds were used to hold the shroud together during this process. When I was satisfied with the fit I then used chopped mat fiberglass cloth and resin to coat both the inside and outside of the shroud. This adds a tremendous amount of strength to the thin sheet metal and makes the shroud much stiffer. The fiberglass was then sanded and the shroud was primed. Holes were then drilled for rivets and the whole shroud was riveted together. The rivets were added because the metal and fiberglass expand at different rates when heated and rivets spaced about every inch or so will keep the glass and metal from separating. Once all that was done the shroud was painted with wrinkle black paint and the whole mess, radiator, fan and shroud were installed on the car. Here is the finished product.

There is approximately 1/2" clearance from the radiator core to the shroud and about 3/4" clearance from the shroud to the fan blades. The fan is about 2/3 into the shroud so this should be just about perfect. Here are some additional pictures.

The final project for this month is to modify the battery tray so that the lower support doesn't interfere with the AC lines. The stock tray has a center support that goes from the outside of the tray to to the inner fender just above the frame rail. If left in place the AC lines would rub against this support and eventually fail. The solution was to move the support to the rear edge of the tray and mount it to the frame rail. This moves the support out of the way and the AC lines are free of interference. This shot shows how the lines run under the battery tray. You can see how a support running from the outside edge of the tray to the inner fender would cause problems. You can also see the new location of the support on the rear edge of the tray.

Here's a better look at where the support was relocated.

That's it for this update. Next I'll be temporarily mounting the driver's seat and doing some final work on the 440 getting it ready for its initial start and cam break-in.

Check back often for more updates...

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