Last updated February 15, 2009
The tech articles on this web site are written with the understanding that you have some mechanical and/or electrical knowledge, and that you know and assume the risks and responsibilities involved in working on your own car. If you decide to make a modification to your car based upon one of these articles, you assume total responsibility and risk for those modifications. In no event will ISOA or any of its directors or officers be liable for any direct, indirect, incidental, or consequential damages arising out of your making modifications to your vehicle based upon the contents of an article provided in this web site. It's your car, and it can affect the health and safety of yourself and others - work and drive safely and wisely! To put it bluntly, if you don't know what you're doing under the hood, then you shouldn't be there.
Here's a 17kB .gif file of the Stag V8 performance curve - Torque, Brake Mean Effective Pressure, Specific Fuel Consumption, and Power vs. RPM.
This drawing was originally published in the April 1970 edition of Automobile Engineer, and was reprinted by the Vintage Triumph Register in issue 38 of The Vintage Triumph magazine. ISOA is a chapter of VTR. Automobile Engineer is no longer published, and issue 38 of TVT is out of print. If you feel that the posting of this image violates your copyright, send an email with the pertinent details to TKBuja@ISOAinsightbb.com to request its removal from this website.
by Tim Buja
Two water pumps were specified for use in the Stag, with different covers used to match the design of the pump impellers. The external appearance of the covers are almost identical at first glance, but small differences can be noted.
The six-vane pump cover has STANPART cast into the side of the cover facing the right cylinder head, and LUNASC in the side facing the left cylinder head. The 12-vane pump cover has STANPART and PBM cast into the top of the cover.
The main intake on the six-vane pump cover is flush with the heater return connection. On the 12-vane cover, the main intake extends about 1/2" further from the heater return connection.
The bottom of the six-vane pump cover is machined at a steeper angle, and a straight edge placed along the right side of the machined surface will intersect the top of the cover to the right of the centerline of the volute. The same straight edge will intersect the top of the 12-vane cover to the left of the centerline.
by Tim Buja
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