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Resto Roundup, August 2014 - Restoration Questions
I would like to ask you to do a comparison and for your opinion. My car is a Metuchen-built '69 Super Cobra Jet, with a build date of 9/19/68. The pictures I sent you are of the SCJ horn jumper wire harness on my car. My jumper harness is blue wire with a yellow stripe encased in a black tube jacket with two plastic box female spade connectors and one spade to female connector. The jumper has no markings or ID whatsoever. How does my harness compare to your horn harness on your own '69 SCJ Mustang with only 11,000 miles? Does mine appear OE? Thanks.
Via the Internet
The horn jumper wire on my '69 Mach 1 is different than the one in your pictures. My car was a Dearborn-built car (2/69). Your car is a very early San Jose–built car. I have enclosed a few pictures of the wire off of my car. The harness from my car is typical of Boss 429 cars as well. Note the engineering number stamped on the wire. It's hard to tell but it looks like the spade on your harness may have been soldered?
Taking a Breather
I have a '67 Shelby GT 500 Mustang. The car is original except for the smog system. I have purchased an original smog system to install in the near feature. This Shelby has only 37,000 miles with 100 percent original Wimbledon White paint. I'm also looking for the special flat-style breather cap for the valve cover that is used on cars with smog. What is the Ford part number? Was it used on other vehicles? I cannot get a lead on one of the breather caps.
The Ford part number for the breather cap you are looking for is C7AZ-6766-A. This breather was also used on '67 427ci Fairlanes and Comets. Very early C7AZ-6766-A caps did not utilize the Autolite script. Most C7AZ-6766-A oil breather caps were Autolite script. The C7AZ-6766-A cap is a rather rare item. I've been told the same style cap was used on '66-'67 Lincolns. These caps, however are black not chrome. If you can find one it can be stripped and chromed.
Vexing Valve Stems
I have a BFGoodrich F78-14 Space Saver Spare that has a double valve stem, I assume it's from a '71 or '72 model year. Can the double valve stem be removed and replaced with an original-style 1¼-inch Dill-style rubber valve stem? The base of the double valve stem appears larger then a single stem? Can the Goodyear tire store near me compress the tire valve stem side enough to remove and put in the new stem without damaging the tire? Any information on this would be helpful. Am I correct in assuming that the single valve stem is correct? Many on the Boss 302 website believe the double is correct?
Brett (last name withheld)
Yes the valve stem can be changed. The valve stem opening is the same size. I have seven cars—all '69-'73s with Space Saver Spares—and all of the wheels are dated and have the single rubber valve stem. I have not seen a metal stem prior to the D40Z Granada wheel. MCA Boss 302/351/429 rules state the use of a single rubber valve stem. I believe that is accurate. Don't forget the clear valve stem cap!
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Send your restoration questions to: Resto Roundup, c/o Bob Perkins, Perkins Restoration, North 2123 Hwy. 16 & 26, Juneau, WI 53039. Send email to firstname.lastname@example.org.