Time to start on this problem. The Discovery will be under significant stress in competition and will get hot FAST. To address this issue we are attacking the problem as follows:
The radiator from the Discovery was shot. It had rust and holes in it so had to be replaced. I had a recently renovated radiator from my old 1988 Range Rover available so we have employed it for a start.
We had hoped to upgrade to a higher flow aluminum radiator in due course with an extra core but the cost was just going to be too high. I had the old radiator re-cored with a 4 core replacement. We had thought of going for a 5 core but were talked out of it given the low speeds that the Disco will endure most of the time. We will wait and see how it works out.
This is an often overlooked item. Since we will eventually be converting to automatic the problem needed to be addressed. Land Rover have a perfectly good cooler for their transmissions. It is round, compact and fits well in front of the radiator. But is it enough. We thought not [due to our years of engineering experience, only joking] so wanted an upgrade. Again I had a spare transmission cooler from my 1988 Range Rover so why not link up the two and get double the cooling for almost zero cost.
The two following pictures show how we did it:
We hooked up the two in parallel by tapping holes into the top of the 1995 [it is actually stamped 1994 on the casing] cooler so that lines could be run up to the 1988 [it is actually stamped 1987 on the casing] cooler. These were then fitted with standard hose fittings as shown in the above left hand picture. We had to separate them when fitted to allow room for the hose fittings as can be seen in the right hand picture above. They provided a gap of 4 3/4 inches between the fins for fitment of an engine cooler [see below]. The holes / fittings between the two vintages of coolers are not exactly the same but are close enough to allow a nice coupling.
To provide additional space for a winch we also flipped the fittings over and located the coolers behind the horizontal support bars. This gives us an additional 5 1/2 inches of room that can allow the winch to me moved back into the car to maintain approach angle.
This was tricky. Because we employed an older radiator with no engine oil cooler fitment a separate external cooler was needed. Given the modifications for the transmission cooler as per above we only had a space of 4 3/4 high x 26 inches long x 2 1/4 inches deep to fit a cooler. I probably spent about 6 hours searching the web to find a suitable cooler for the space. In the end I purchased a Specialty Auto Tech cooler. It is 24 inches long and 3 inches in diameter.
The cooler on the left with a double tube allowing for fitment on one end only is the design we went for. As the inlet and outlet tubes are on the one side [passenger side] this was the logical choice over a straight through design. The cooler has not yet arrived so I will post some pictures once it has been fitted between the transmission coolers.
The following is some stats from their website:
The toughest coolers on the planet are designed to cool any vehicle fluids including:
Automatic transmission fluid
Power steering fluid
Now available in a new 2-pass design for greater efficiency and ease of installation !!
Heat sink design has internal & external cooling fins to transfer heat & minimized the need for direct airflow
Compact design, 3” diameter, mounts in tight places, even on frame rails away from confined spaces between grills and radiators
Cools better than conventional coolers when you need it most under 40 MPH. Sturdy welded aluminum construction withstands the toughest operating conditions such as flying road debris. Contains pressure up to 3,000 P.S.I. High fluid capacity adds 1/2 quart per foot of cooler length. 2 Quarts for our 24 inch long version.
Power Steering Cooling
We are using a prototype replacement power steering pump configuration from Rover Tracks. This comprises of a Saginaw Power steering pump and reservoir in one unit. The reasons we went this way was that they are far cheaper than the Land Rover product and provide more power than the standard unit. Rover tracks are building a kit to allow a bolt in set up. To aid in this we decided to install an external cooler just to help keep the power steering working all the time. Not something that 99% of Four Wheel Drivers would need.
A Perma Cool unit has been purchased and installed. The left hand picture is the kit provided and the right hand picture is it installed in the vehicle. Note whilst this appears to be a great location installation was a real pain in the butt so if you are contemplating using such a cooler consider an alternate mounting location.
This unit fits to the outlet side of the power steering box on the return to the power steering ump. I have copied the following from the Summit Racing website.
I'll show some pictures once it is installed. I hope to put it under one of the horns at the front of the Discovery.
OK OK I am paranoid about overheating. Since we removed the air conditioning cooler which will not be needed as we will not have air conditioning. Space became available in front of the radiator. The Discovery comes with 2 electric fans that are normally fitted in front of the Air Conditioning cooler and activated when needed for the air conditioning. We reused these and fitted them inside the Air Conditioning cooler bracket allowing them to be fitted straight in front of the radiator and still allow room for the transmission coolers which were fitted behind the diagonal support bars. These are to be wired up for manual use if the engine starts to get hot or we are operating at very slow speeds when wind flow is not sufficient to maintain a good temperature. They will also help suck air past the transmission and Engine Oil coolers. The below picture shows the fans in the revised bracket and the Right Hand picture above in the Transmission cooler section shows them installed in the Discovery.