Project Camaro–Banks Power: Ducting and heat exchangers for Project Camaro

When packaging twin turbos and dual intercoolers under the hood of Camaro that has had the engine relocated, you have to make all of the necessary ducting.

Where do you buy special steel combination air cleaner housings and cool air ducts? The answer is you can’t buy them, you have to make them.

Click thumbnails for a larger image

The process begins by envisioning the shape of the desired unit. The shape will have to fit the space available as well as the intended air filter element. Then the time-consuming task of shaping a wooden “buck” begins.

Working in a grinding booth to control dust, Speed begins shaping the and smoothing the wooden bucks.

Ducting and Heat Exchangers Manage the Heat

As Gale Banks likes to say, “It’s all about airflow”. He’s usually talking about the power-making airflow through an engine when he makes that statement, but there are other kinds of airflow that have a big impact on power too. One is getting cool airflow to the induction side of the engine, such as through cool air hood scoops or ducts. The Camaro utilizes custom-made, all steel cool air intake and filter housings that open into the grill area to achieve intake airflow in sufficient quantities to supply the dual turbochargers that feed the high-horsepower engine. Steel was selected to make these assemblies durable during routine service.

Another generator of heat is the compression of the air by the turbochargers. Whenever air is compressed, it is heated, and this is true of the high-pressure boost air coming out of the turbochargers. Cooling this pressurized air by passing it through dual aluminum air-to-air heat exchangers (intercoolers) on the Camaro both improve air density and helps prevent engine detonation (see ”Cool Air Equals Power” elsewhere on this site). The ductwork and housings for these dual GBE Techni-Coolers™ intercoolers, which are positioned just behind the air conditioning condenser and in front of the high-capacity Griffin® aluminum radiator, were, like air intake and filter housings, custom fabricated by Rick “Speed” Lefever. In this case, aluminum was selected to help dissipate heat. The dual intercoolers are vertical flow units that take in the hot pressurized air at the bottom and expel the cooled air at the top. It is then ducted into the engine.

When the Camaro is in motion, airflow through the grill feeds the air conditioning condenser, intercoolers and radiator, but adequate cooling airflow while stopped or at very low speeds is the job of the engine fan. Efficiency of the fan is directly related to the shrouding transitioning from the radiator to the fan. Look closely at the construction photos of this fan shroud. It was handcrafted from aluminum by Speed.

In most cases, creating these unique and involved ducts, housings, and shrouds first requires making a wooden buck. Shaping the buck is a major job that’s part woodworking and part sculpture. The sheetmetal is then formed over the buck in various pieces and sections. The forming requires the skilled use of hammers, dollies, and an English Wheel. The parts are then welded and blended together to make the final pieces. It’s a very time-consuming, labor-intensive task that’s a blend of art and fabrication, with a healthy dose of science and engineering thrown in for good measure, and Speed is a master at doing it. Can you say “metal magician”?

Click thumbnails for a larger image

	1) In this case both left and right air cleaner housings were required, and that meant shaping two mirror-image bucks.	2) With the bucks completed, steel sheetmetal was carefully hammer-formed over the buck. In this case, the forming required multiple pieces of metal, which were then trimmed and welded together.
	3) After careful welding and filling, the pieces were filed and sanded. The result is that multiple pieces look like one single piece when finished. This is the art of metalworking, and Speed is a master.	4) Additional sheetmetal was formed and welded to build the full housing.
	5) When finished, the housings were polished to a high luster with #1500 paper.	6) Looking through the front wheelwell shows the housing in position behind the grill. These housings were designed for high-flow K&N® air cleaner elements.
	7) Shown here are the dual air cleaners with their direct ducting into the turbocharger compressors.	8) The air conditioning condenser is the first heat exchanger to get cool air through the grill. Note the custom saddles to support the dual, side-by-side intercoolers and high-capacity aluminum radiator.
	9) The high-capacity Griffin® aluminum radiator is the rearmost element in the heat exchanger “stack”. It sits in its saddle and is supported on each side by mounts to the front roll cage downbars. Rubber cushions are used between the saddle and mounts to provide some flexibility without damaging the radiator. Note too that cardboard is taped in place over the radiator fins during fabrication. This prevents unsightly fin damage.	10) The right lower A-arm mount had to be notched to provide room for the lower radiator pipe and hose.
	11) After the radiator was mounted, Speed fabricated an aluminum fan shroud to optimize airflow through the air condition condenser, intercoolers and radiator.	12) Shaping and welding the fan shroud was another time-consuming process. All welds were smoothed for a finished look.
	13) With the radiator and shroud in place, the dual intercoolers were fabricated to fit between the air conditioning condenser and the radiator. Air from the dual turbocharger compressors is routed from the compressors to the bottom of the intercoolers. This required more special ducts.	14) With the radiator removed, Speed began fashioning a wooden buck for the duct from the bottom of the intercooler to the compressor outlet on each side.
	15) The finished wooden buck transitions smoothly from the oval mouth at the bottom of the intercooler to the round compressor outlet.	16) Aluminum sheetmetal was formed over the buck to make the duct. Both right and left ducts were needed.
	17) The ducts were fashioned from two pieces of aluminum, and then welded together to make the finished duct.	18) Shown is the left side intercooler duct in place. An additional duct elbow will be added to connect the lower duct to the compressor outlet (blue hose coupling).
	19) This photo shows the complexity of duct routing. The dual air cleaners are at the outside with the intercooler return ducts turning in toward the engine. These ducts will eventually route into the fuel injection air box atop the engine. Note too that the bulky hood springs have been replaced with compact gas struts.	20) This photos shows the depth of the air conditioning condenser/intercooler/radiator stack, and why the engine needed to be set back 6 inches to allow room for the fan and ductwork. It’s all about airflow!