[Tominator]

My Ranger has a 5.0 and James Duff custom radiator designed for this application. Eveything in the system is new or nearly so. 180 Mr Gasket stat.

Had 2 10" spall pullers and temps would get to 240 at idlw in a closed garage about 90 ambient. On a 100 degree day moving it will stay around 220. It has AC but until I've solved this problem it's useless to even try it.

I've a supercharger to install and it will add to the load of course.

Took everything apart and moved radiator forward slightly and sealed radiaror to header. Mounted 10" pusher on RHS and 14" puller to left....can't use flex fan or single fan because of clearance to WP pulley. Installed Evans Cooling waterless coolant.

Now temps stay under 230 but if I turn on the heater and run the fan engine temps go down 20 degrees in a matter of minutes. Radiator too small and not enough air flow is my guess.

No room, for bigger radiator. No room for larger fan BUT there is room under the bed under the high mounted flowmasters! A local shop can fab an aluminum ducted mount of my design. With the added coolant and lines my guess is the same radiator can be used with a 16" fan and my problem would be permanently solved! I'm going to look under it this weekend and check for room for coolant pipes.

Any suggestions on this location or other comments mucho appreciated!

[farna]

There's another way. I've seen "auxilliary radiators" sold in J.C. Whitney catalogs. Basically it's a small radiator to add additional cooling capacity. Mounts in front of the existing radiator like a transmission cooler --- looks about the same only a bit larger. What I would suggest is you mount on of those under the truck with an electric fan. Use two heater valves coming off the heater hose. Mount a "Y" in the heater hose andthe two valves after the "Y" -- one valve for the heater, one for the auxilliary radiator. Or a two way valve in the auxilliary rad line. Then you can cut flow to the auxiliary when not needed. In the winter the auxilliary might cool to much for the heater to work properly.

You can "roll your own" auxilliary radiator. Either use a largish heater core or look at some of the small cars that have really small radiators. An Audi 5000 comes to mind because it has a small offset radiator, but that might be to big. I'd use a fan on it instead of a scoop arrangement. There will be some airflow even without the scoop. Use a thermostatic switch to control the fan.

[Kruzin Karl]

You didn't mention if you're using a fan shroud or not, but I didn't see one in your pics. A fan shroud will make your fans pull all of their air through the radiator, would make a huge difference.
Also, an Explorer V8 radiator would bolt directly in, and might possibly cool better than your aftermarket one. The one I put in my Ranger was an exact bolt in fit.
Good luck - Karl.

[Tominator]

I'd thought about the auxilary radiator but I'm unsure if it's capacity would make enough of a difference. I've got my eye on a Mustang intercooler, but it's too long to add a fan to.

I do have a Ford Racing oil coolerr that's going in and just might try another one mounted side by side but run coolant through it.

How about rerouting the bypass hose for this purpose? This is not may daily driver and sits out the winter in a garage.

A fan shround is not really practical because of one fan pushing and the other pullong. The electric fans are mounted flush to the radiator and would not pull through the complete surface unless mounted slightly behind the radiator and to a shroud. No room for this.

The present setup is a 10" pusher and a 14" puller. To make room for the lower super pulley the 14 has to be reduced to a 12" and that compounds the problem even further.

I'm not sure the explorer radiator has any more capacity than what I've got and there is still the problem with not enough room for a fan of any size. Guess I need to look at one to tell.

Remember, that with the supercharger I'm looking to overkill the solution so to speak. The solution that might work now might not under boost.

Thanks for the help and keep the suggestions coming.

I'm going to do same more measuring tomorrow...both fore and aft!

[cboy]

I have a rear mounted radiator in my '31 roadster and have had mixed results cooling my engine. In fact, I've ended up having to mount a small second radiator (from a Mazda truck) in the normal front position in order to keep the system in the 190 degree range where I like to see it. For what they are worth, here are a couple of my observations.

1) The rear mount will GREATLY reduce air flow through the core no matter how you try to tuck it up into the chassis. Also, depending on it's position, you can pick up a LOT of very hot air coming off your engine, trans and exhaust system which will reduce cooling efficiency.

2) I can't be absolutely sure of this but I believe one of the largest problems with rear mounted radiators is the plumbing. In order to route the cooling to the proper locations you need a large number of angles and bends in the plumbing to get your coolant from point A to point B. Each one of these bends creates a major reduction in overall coolant flow. Add them all together and you get very inefficient system flow. I installed a new high flow water pump but I feel it is still under-powered for all the corners I have push coolant around.

3) Pay attention to the air flow EXITING the radiator. I found that heated air exiting my core was getting trapped under the car and then forced around the sides of the radiator only to be sucked right back through the core. Very inefficient. I ended up adding a shroud as well as some sheet metal air dams on the "exit" side to remedy to situation, but it's still far from perfect.

Keep us posted on what you come up with. Cooling can be a real challenge at times so posting your innovative solutions will be a great help to all of us.

[Tominator]

Good info cboy !

Some thoughts...plumbing would be a chore. 1.5" alumuminized exhaust tubing but it will indeed be exposed to the engine compartment and exhaust.

In a perfect world there would be no pump cavitation and since liquid cannot be condensed or compressed I would think the number of bends would make little difference....but of course the pump design is the limiting factor.

Evans recommends deleting any WP bypass for race cars and I'm sure that is to force all coolant through the radiator....but this is a street machine...

Keep the thoughts coming!

[Kruzin Karl]

Is your James Duff radiator mounted in the stock location, or is it one of those installs where they notch the radiator support and install it slightly towards the engine?
I still think that some type of shroud that makes the fans pull all of the air through the radiator would make the most difference. If you dont have a shroud, you can actually be sucking hotter air in from the engine compartment, as someone above mentioned.
I've heard of people relocating the radiator further forward under the support, towards the grille, opening up a lot of space for larger rad, fans, shrouds, etc.
Well, good luck. Later - Karl.

[cboy]

Originally Posted by Tominator

...I would think the number of bends would make little difference...

The "physics" of what happens inside the plumbing is well beyond me so I can't argue your logic. I do recall reading about the restrictive forces resulting from sharp bends (like 90 degree turns) in the system...but unfortunately I can't lay my hands on the link(s) at the moment. Seems to me there was something on the order of a 10-20% reduction in flow for every right angle in the system. If you haven't done a search here on HR.Com. it might be worth a shot. I know we've had some good discussion on the issue in the past.

I do know that I'll probably never attempt a rear install again. I think I would have been better off just investing in a very large core radiator built to fit the '29 grill shell. Granted, it would have cost me a bundle up front and I wouldn't have learned nearly as much about how to tackle such a system, but it sure would have been a lot less headache. It's functioning well now, but it was a real struggle getting it that way.


However, your situation is a little different. As I understand it you are basically looking at installing a "secondary unit", sort of like a "pre-cooler". And for your purposes a fairly inefficient flow etc. might not matter quite as much as in my system where I was attempting to use the rear mounted radiator as my primary (and only) cooler. Actually, I'm a little surprised your existing system, just as it is, does not perform a little better. I guess I'd think a lot more about a different fan/shroud set up before I'd tackle all the obstacles involved in trying a rear mounted radiator.

[home brew]

[QUOTE=Now temps stay under 230 but if I turn on the heater and run the fan engine temps go down 20 degrees in a matter of minutes. Radiator too small and not enough air flow is my guess.[/QUOTE]

If you can drop the temp by 20 degrees with your heater why not install another heater in the rear and run coolant hoses to the rear and use that as your mini rear mounted rad. Solves the problem of size and of bends in the system.

[Tominator]

Originally Posted by Kruzin Karl

Is your James Duff radiator mounted in the stock location, or is it one of those installs where they notch the radiator support and install it slightly towards the engine?
I still think that some type of shroud that makes the fans pull all of the air through the radiator would make the most difference. If you dont have a shroud, you can actually be sucking hotter air in from the engine compartment, as someone above mentioned.
I've heard of people relocating the radiator further forward under the support, towards the grille, opening up a lot of space for larger rad, fans, shrouds, etc.
Well, good luck. Later - Karl.

The James Duff radiator is designed to go under the radiator support. The upper hose connection prevented it from going further forward. I notched the support and gained about a half inch. I then sealed the radiator to the support with stick on foam. There are two openings in the radiator support and the radiator completely covers the openings.

Did some measurements yesterday and due to space limitations a full size radiator will not fit under the bed.

I could put a small radiator in front of the AC condensor but no fan. That might be the place the oil cooler goes.

There is space under the radiator and if the auxilary is mounted at a 45 degree angle there is room for a couple of fans. Looks like I need one that measures 18X10 and a maximum of 3" thick

BUT.....amazing what a strong hot cup of coffee can do ....If a flex fan that is less than an inch thick at rest and compatible with reverse a reverse flow WP could be found a mechanical fan/shroud might be the ultimate solution.