This is actually better than...
This is actually better than what we started with. A generic, oversized battery was placed on the battery tray with nothing to hold it in place. To get it to its place of surgery, we replaced it with an Optima red-top battery and strapped it down the best we could. This is not recommended for long-term!
I've had lots of experience with early Chevys, but it's about time I expand my horizons. I'm a fan of the SCCA Trans-Am series of the late 1960s and early '70s, and visualized my Camaro to follow that theme. Over the past seven years, my '68 Camaro took a path more on the tame side. This Mustang is my opportunity to build up a brutal, no-nonsense street-legal race car with a license plate and functioning headlights.
We bought this 1966 Mustang as a barely running straight-six automatic. Knowing in advance that most of the drivetrain and suspension components would be replaced, it didn't matter much what the car started life as. Of course, the first day we went to drive it after the sale, it didn't start. The battery was dead, and once we put the new one in, it cranked forever without even a backfire to assure that there was fuel or spark. I believe it's the car's way of telling us it's ready for an upgrade.
There will be no stereo, no A/C, no carpet, no over-the-top fancy polished pieces to distract you from its pavement-pounding roots. The objective is to build a lightweight, all-business street car with style. The playbook contains a full coilover suspension, rollcage, big disc brakes, a pump-gas high-rpm small-block, and two race seats.
The last 35 years of technology will have its place in the car; modernized instrumentation and suspension will fill the voids that parts from the 1960s couldn't. We'll be borrowing tricks picked up over the years to make this car perform effortlessly. My own touches will be evident as well: orange paint, satin finishes, and a downplayed look on performance parts.
The first order of business-lightening things up-was inspired by our October 2008 story called "Lighten Your Load." In a nutshell, I decided to take my own advice. Weight in the front of the vehicle is detrimental to the car's handling at the road course and the dragstrip. Around the corners, weight on the nose makes the car more prone to understeer, a less-than-favorable way to get around the track. At the dragstrip, for optimal rear-wheel traction, the weight needs to transfer rearward, where every pound helps.
An easy, cost-effective way to help move the weight to the rear is to relocate the battery to the trunk. Moving a 40-pound weight from the most forward location possible to the most rearward seems like a no-brainer. There are other advantages that come along with the newfound space up front. The overall cleaner look of the engine bay and the race-car look of the battery box can be incentives. For my situation, it was a mandatory move. Early Mustangs suffer from an overcompact engine bay that limits the radiator size you can use. The factory unit looks like it would be more at home in front of an import than a fire-breathing V-8. In Southern California, the cooling system is very important, and to make room in an early Mustang, the battery needs a new home.
We picked up a battery relocation kit from Taylor Cable, put together specifically for our Optima battery of choice. We like to use the Optimas because they won't leak, and can be mounted in any orientation. The battery relocation kit comes with the box in three pieces (bottom, body, and lid), positive battery cable and terminals, ground cable, cable retainers, vent tube, hold-down assembly, and all the hardware to make it work. We only needed to make one trip to the parts store for a longer ground cable to fit our specific routing plan.
 This is an all-too-familiar...  This is an all-too-familiar sight. It seems like all old cars suffer from a corroded battery tray due to years of leaky batteries sitting in them. This piece went straight into the trash can upon removal. |  The first task is to figure...  The first task is to figure out where to mount the battery box. It should be a flat, level place that's not so tucked in that the battery can't be removed easily. At this time, you should study the underside of the car to determine if the holes for the battery box retainers will be accessible. Watch out for the gas tank, leaf springs, and other undercarriage items that can get in the way. Sometimes there will be brackets in the way that will need to be removed for proper installation. |  Set the bottom plate down...  Set the bottom plate down as a template, and mark where you will need to drill the holes. Whiteout works well to mark the floor, since it stands out over any color. |
 Use a punch to mark the middle...  Use a punch to mark the middle of the whiteout and help guide the drill bit straight. These floors are often pretty hammered, and can cause the drill bit to wander. |  With a heavy punch, you can...  With a heavy punch, you can start drilling your holes with a step-bit. I prefer this so there is no need to change drill bits to get to the next size. |  The all-thread supplied in...  The all-thread supplied in the Taylor kit was longer than needed, so to figure the correct length, drop it through the top of the box and mark how much to take off below the floor. We wanted a little extra to protrude past the lid to be safe. |
 The floor and the bottom portion...  The floor and the bottom portion of the box are sandwiched between two sets of nuts. It is really easy to warp the bottom of the box when tightening if the floor isn't totally flat. To help this, we added shims. Also, as a safeguard, we jam-nutted the bottom of the studs to guarantee they won't come loose. |  Next, place the battery between...  Next, place the battery between the newly installed all-thread and slip the battery hold-down over. Now is the best time to tighten everything. The all-thread may not want to stand up straight, and there isn't a way to correct this once the box body is on, so slip the lid over the studs while you tighten the hardware. This will make the box easier to cover with the lid later on. |  Now that the battery is in...  Now that the battery is in its new location, you will need to find a ground. The frame is the best place. There are a couple options for attaching the ground cable. We found an unused hole, and welded a nut to the face of it so we could use a bolt to attach the ground. I've seen a lot of people simply thread the bolt into the sheetmetal, but this is way prone to stripping. |
 The Taylor kit comes with...  The Taylor kit comes with grommets that fit the cables perfectly; you will just need to drill holes through the floor to insert them. We recommend using a step-drill for this, too. You'll have to make sure there is ample room for the cable to be routed on the bottom side of the hole. Repeat the same operation for the positive cable. |  The Taylor kit also comes...  The Taylor kit also comes with plastic cable retainers to fasten the cable along the length of the car. Make sure to route the wire away from any moving or hot parts because if the insulation is rubbed off, the cable will arc and can cause a fire. We ran the cable along the outside of the framerail, and then brought it back in before the leading end of the leaf spring. A good place to route the cable is along the inside of the subframe connector, if you have one. |  Once the cable finds its way...  Once the cable finds its way to the engine bay, route the cable as far from the engine as possible. Since this is a Ford, it goes to the starter solenoid, usually mounted on the passenger-side fender, but for other makes this cable would go to the starter, where we would suggest you put a high-temp sleeve over it as a safety measure. |
 Here's the finished installation....  Here's the finished installation. We're really happy with the way it turned out and look forward to building the rest of Project Street Fighter to match. | | |