Abstract: A heat exchanger includes a metal tank having an open side and a flange around the open side, and a metal header plate connected to a plurality of heat exchanging tubes, the header plate having a channel around its periphery for mating with the tank flange. The cast metal tank has predominately thin walls and at least one cast indentation point for starting a drilled hole. The indentation point is located in a defined, limited region of the tank walls having a thickness greater than surrounding wall regions. The indentation point may be drilled out and, optionally, tapped, to form an additional access opening in the tank.

Abstract: Apparatus and methods for simulating varying atmospheric conditions comprises an enclosure that is sealed except for an air inlet and an air outlet by means of which air is admitted to and exhausted from the enclosure. The inlet of the enclosure is connected to a compressed air source and the outlet of the enclosure is connected to a vacuum pump. Adjustment of the flow rates of air into and from the enclosure results in changes in the air pressure within the enclosure to simulate barometric pressure changes from below to well above sea level. Air admitted to the enclosure is temperature and moisture conditioned to simulate changes in atmospheric temperature and humidity conditions. Apparatus and methods according to the disclosure are particularly suited for the testing and calibration of vehicle carburetors.