Installing Radiator Baffles
By John Trifari
Originally published in the Austin-Healey Magazine, August 1995
Several years ago Geoff Healey wrote an article in Chatter in which he described a technique for keeping Healey engine temperatures down. Apparently he discovered that the open spaces at the side of the radiator were causing hot air that had passed through the radiator to re-circulate, dramatically increasing temperatures. By adding baffles to each side of the radiator and forcing all air flow through the radiator, he could idle the car in a closed room with no noticeable increase in operating temperature.
Norman Nock of British Car Specialists in Stockton CA gave me the first hint of the importance of baffles when I first started editing Austin-Healey Magazine. He suggested that I use blocks of foam to close off the open spaces at the side of the radiator on my BNI, and I used that approach until I decided that a more permanent solution was in order. The result was two baffles I custom-fitted to my BNI. They use the four mounting brackets and screws used to secure the radiator to the frame, and take advantage of the bracket on the radiator halfway up each side. To prevent flutter, the left-hand baffle is also screwed down to the radiator support on the left hand side. The ends of both are screwed to the fender wells via angle brackets.
Figure 1 shows the left hand baffle facing forward (A). Note the cut-out for the headlight wiring (B) and the steering column (C). The actual left-hand baffle is shown in reduced form in Figure 2. Figure 3 (A) shows the right-hand baffle. Note the way the top is cut to accommodate the air vent tube. The right hand baffle is shown in reduced form in Figure 4.
Both baffles were created from cardboard templates that I made up using the time-proven hit and miss method. Use the dimensions shown in Figures 2 and 4 as a general guide to the creation of a set of templates for your templates. Once I had the templates cut to my satisfaction, I transferred the pattern to pieces of metal flashing. I cut the baffle out using tin snips. This was my first real experience cutting sheet steel, and it wasn’t fun. It was like using a double-edged razor blade to build a model airplane—all over my hands were these angry little cuts. If convenient, handle the baffles with gloves. In any event, the edges of both baffles were covered with duct tape to permit easy(and safe) handling (be sure to put edge protection on the cut out where the headlight wire passes through the left-hand baffle in front of the relay.) Also keep a bottle of iodine handy. Better yet, don’t use flashing. Something that’s slightly thicker and less pernicious—like aluminum—might be better, although a thicker baffle is more difficult to twist around the steering column.
To mount the left-hand baffle, I positioned it and made any on-the-fly modifications with my tinsnips. Then I marked off the mounting holes on the radiator where I was going to mount the baffle through the radiator stays and positioned the angle bracket on the left fender well. Then I drilled all the mounting holes in the baffle, and painted it. To mount the bracket down I first unscrewed the lower radiator mounting bolt, and re-mounted it through the baffle, repeating the process with the upper bolt. Then I ran a bolt through the baffle and the upper radiator mounting bracket (see D Figure 1), and used a sheet metal screw, to secure the baffle to the middle mounting bracket on the radiator. (See E Figure 1). Then I screwed down the angle bracket needed to secure the end of the baffle to the fender well. The right baffle went easier since I didn’t have to wiggle it around the steering column and worry about the headlight leads. Again, the baffle was mounted to the radiator through the mounting brackets. Then I used a sheet metal screw on the middle bracket, and mounted down an angle bracket at the end (see B Figure 3). One tip in installing the left and righthand baffles: don’t tighten everything down until all bolts have been positioned.
The results seem to have justified the iodine I used on my hands. Running temperatures typically do not exceed 165°F in normal running, even during a recent heat spell we had on the Coast. Car temps have occasionally hit 195°F when the car is driven up a long grade. Hope all this has been thoroughly baffling.
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