Headed In The Right DirectionI own a '67 S-code GT convertible. I had aftermarket headers on for a while but became tired of the small exhaust leaks and the flanges riding so low to the pavement. I ended up taking them off and replacing the stock exhaust manifolds. I miss the power and the sound, though. I am thinking about using a pair of Ford cast-iron headers. I saw a photo of one on a 406 in the July 2000 issue on page 22, which Jeff Ford reported was identical to a 390. My heads are two-hole-per-exhaust-port heads, so which type of cast-iron headers would mount up, and of those, which would fit the Mustang chassis without modification? Or must I switch to 428 four-hole heads?
Second, with the price of gas lately, I am looking for ways to cut back. During the European Mustang run across America in the mid-'80s, I still recall a '68 Shelby GT500 matched up with a five-speed manual transmission. Which type might that be? My car originally came with a four-speed, but I recently dropped in a C6 auto for get-around-town ease. Is there a five-speed manual available? How about an AOD? I don't want to make any serious modifications to the car. I am really looking for something I can drop in that can get the engine revs back down, while cruising down the highway.
Third, it is a nonair car, but I am considering investing in an A/C system. How will the value of the car be affected if I opt for an aftermarket, nonoriginal in-dash unit, as opposed to spending an additional $700-$800 to install a more original-type system? My car is a daily driver with minimal modifications (a rear sway bar, traction bars, an aftermarket Holley carb, a '67 PI high-rise aluminum intake manifold, and dual mufflers, among other things) but has otherwise retained a pretty stock appearance. Your opinion would be appreciated.
Last, also on page 22 of the July 2000 issue, the finned taillight panel on the '67 fastback has fins all the way across the taillights. Mine doesn't. What gives?
Please include a year's subscription with your answers. You guys are great!Eric HeitmanHolland, MI
Free-flowing cast-iron manifolds will indeed increase your performance, compared to the restrictive stock units. I suggest you obtain a set of 428 Cobra Jet manifolds, since they are similar to the 406 units you mention; however, they are designed to fit the Mustang chassis. The exhaust H-pipe will also have to be changed, because the manifolds are much longer than the stock pieces. They should bolt to your existing cylinder heads with no problem.
Five-speed overdrive transmissions from late-model Mustangs have been adapted to early Mustang chassis for many years now. Most are behind small-block V-8 engines; however, big-block transmissions utilize the same bolt pattern and are otherwise dimensionally identical to their small-block counterparts, except for the input shaft length. I'm sure a five-speed could be installed with the correct length pilot bushing and correct bellhousing spacer available from most Mustang suppliers. A better and stronger swap would be an automatic/overdrive unit available from LenTech Automatics in Ontario, Canada. The folks at Lentech have developed the AOD transmission to handle any situation and can custom-make a unit to fit in any application. Call Len Bertrand at (613) 838-5390.
The installation of a nonoriginal A/C unit will not hurt the value of your vehicle, in my opinion. Since you are not worried about car show points and the quality of the new add-on units, duplicate the factory system in both appearance and function. I think the addition of A/C is a wise choice.
The taillight panel pictured in the July 2000 issue is not the piece actually produced by Ford. I assume the photo is of an early prototype used to promote the future '67 models.