Did early, or any other, Cobras used British Smiths gauges? If so was the temperature gauge mechanical or electric? If electric did they use a British "straight thread" or a standard U.S. "pipe thread" on the sender? I am trying to figure out what is correct for early Cobra & Tiger aluminium intake manifolds, "straight thread" with a sealing washer or pipe thread. Thanks, David Franchi
David, If I was home I could give you some pretty straight answers, but I am on the road so I cannot check for sure. I believe the early Cobras used a mechanical Smiths with a straight thread and I think the Tigers also used a straight thread, but it was electrical. I will be home in a week and can check on the Cobra application (don't have a cobra, but my Ace has a 289 and is set up the same way) , but I have sold my tigers so all I have is my memory. I will also check the set of '60s era Stewart Warner gauges that came with my Ace and see what the SW gauges were if that helps. Jay Peterson
David, I am home now and checked what I have. My old tiger sending unit is electric and is tapered. My Smiths gauges (have a couple of extra) are Mechanical and (according to Rinsey Mills book)were fitted to some early cars and when the buyer wanted Smiths. The Smiths have a regular "bulb" which has a collar that appears to be SAE straight threads. It attaches to an adaptor with a hole large enough to allow the bulb to go through and is SAE tapered into the manifold and straight on the top to allow the collar to attach. The Stewart Warner temp gauge gauge is electric but I do not have a sending unit for it. Jay
Thanks Jay. Is the Smiths mechanical sender 5/8"x18 thread? Does it use a sealing washer? David Franchi Link to photo of Tiger Smiths sender with 5/8"x18 straight standard bolt thread and a Ford 3/8" NPT pipe thread adapter slipped over the Smiths "bulb" as a comparison. http://pic12.picturetrail.com/VOL439/2051017/12780240/188369830.jpg
David, On the Smiths I have seen (and have), there is no sealing washer and the collar nut and bulb are seperate pieces. There is a flange on the top of the bulb and when an adaptor is screwed into the collar, the flange is sandwiched and provides the seal at the top. The bottom of the adaptor is NPT and then threads into the manifold. As for the size of the adaptor, 5/8 sounds about right but I am not sure. If you can give me a direct e-mail, I'll get a pic of what I have and send it directly to you. Jay
