Build Objective

A period-correct street oriented version of the 1965 AC Cobra (see Legacy of the FFR Roadster), incorporating current technology that improves performance and safety without impacting vintage look and feel, is our objective. See original 1963-67 Cobra specifications and the specifications for this build. Vintage details include:

• engine in the 350 HP range which is the average between the 289 and 427 AC Cobra original engine's power output; the 1963-65 Cobra used a 289 in³ (4.7 L) small block Ford Windsor V8 that generated 270 HP, while later 1965-67 models featured the Ford 427 engine with 425 HP (the higher horsepower was useful only for racing since the vehicle's light weight limited the amount of torque that could be applied to the rear wheels in normal driving conditions)
• classic air filter/carburetor appearance under the hood but with modern fuel management technology
• independent front and rear suspension to mirror the exceptional road handling characteristics of the original car
• Halibrand-style vintage wheels but with DOT-approved 5-lug attachment rather than pin drive racing spinners
• leather racing seats fashioned after the original AC Cobra street roadster design (racers had vinyl seats)
• authentic dashboard with padded covering and vintage gauges, but with modern signal and warning indicators
• British Racing Green body color (also known as RAL 6005) to honor the Anglo-American collaboration between AC Cars Group Ltd., a specialized British manufacturer, and Carroll Shelby, the American automotive designer and race driver, that created the Cobra legend; see 1963 AC COBRA Mark I, British Racing Green gallery, and Legacy of the FFR Roadster section.

The build objective is not, however, a pure street version. Racer style side pipes and roll bars will be retained, as well as the Lemans style gas cap.

The best current technology match to the original Cobra Windsor V8 is the Ford 302, a small block V8 Windsor introduced in 1968, that, when modified by Ford Racing, generates 340 HP. The original 289/427 Cobras used a single Holley four-barrel carburetor (shown below) to allow expert pit crew adjustments for track conditions, including altitude and air moisture.

1964 Cobra 289 with classic pancake air filter over Holley carburetor

Modern electronic fuel injection (EFI) provides a smoother, more dependable engine response to quick throttle transitions, rapid engine starts, reliable operation at temperature extremes, reduced maintenance intervals, higher fuel efficiency, less gas vapors, and eliminates the need for a choke when starting the engine cold.

Our Boss 302 engine will replace the traditional Holley carburetor/air filter pancake setup with a Mass-Flo EFI system that retains the vintage “pancake” air filter look but with the advantage of modern EFI technology.

Our 302/EFI combination should faithfully replicate the engine feel of the original car. With the more rigid air frame chassis now provided by FFR to handle the torque output of the 340 HP 302 engine as well as modern tires and suspensions, our Mk3 will achieve outstanding performance comparable to the 1965 originals. See Ford Boss 302 Engine.

The standard FFR 3-link live axle suspension, common on Mustangs, is most appropriate for drag and smooth track racing.

Our street application will benefit from the superior ride characteristics of independent rear suspension (IRS), and FFR provides an kit modification for this purpose. A passenger side roll bar, while not strictly period-correct, will be included for extra protection.

Early Cobras had 15-inch single 6-spoke wheels with spinners that permitted a rapid tire change during a race. The 427 Cobra wheel interlaced two 6-spoke Halibrand patterns, as shown in the photo of a 1966 427 example that recently sold at auction for $1 million. Cobras used a wider rear tire to better handle high torque acceleration; typically a 7.5” width in the front and 9.5” in the rear.

Our build will use 17-inch Team III wheels with the Halibrand design, but modified for a modern 5-lug attachment; the race track spinner is not DOT-approved for regular street use. However, the replica Halibrand wheels feature a non-functional spinner with lug nut covers, so the overall appearance exactly mimics the vintage look. The specification is 17×8 and 17×10.5 wheels (slightly larger than the original Cobras) with 245/45 R17 and 315/35 R17 modern high performance tires, front and rear respectively (see wheel and tire measurements).

There are three basic bumper options: the traditional racing style quick jacks, the street style over-riders ¹⁾ with or without hoops, or no bumpers at all. Quick jacks come with the FFR 3.1 Complete Kit, while the over-rider/hoop option is about $700 FFR 11130 kit. The quick jack mounting holes can also be filled for a smooth no-bumper look (the mounting holes are not filled in on the front no-bumper example below).

In addition, the front brake duct opening can be left open or covered with a $30 mesh FFR 12469. The top left photo above shows an uncovered duct opening; the other front photos show the duct mesh covering.

The Breeze 35201 hood hinge, part of the EzePak kit, solves the interference problem between the hinge arms and the radiator that can occur with the FFR hinge system. The Complete Kit also includes external trunk hinges that can cause interference between the top center of the trunk lid and the body when the trunk is opened. The Breeze 35200 trunk hinge allows for horizontal and vertical adjustment after installation.

The black dash uses the classic layout in a single FFR aluminum piece with classic style gauges. Firmer support is provided by an Under Dash Filler Panel ($35) that can also mount a 12v accessory power socket ($20). Covering is black vinyl with foam padding that corresponds to the look of the original. Other possible customizations include a passenger side grab bar and wood or vinyl transmission cover.

A drivers dead pedal and transmission tunnel air vents for ventilation offer greater comfort for extended trips. For easier maintenance access, a removable footbox top (hood access), transmission tunnel top (cockpit), and fuel tank sender unit access cover (trunk) are easy to fabricate.

The traditional racing Cobra is painted with two over-body stripes with a 1-inch gap. Special stripe treatment includes ¼” pinstripe boundaries on the main body stripes, and ghost (de-emphasized) stripes. Street versions often drop the stripes for a single color paint job. See BRG example and also 1, 2, 3, 4 (Ivy Green example at right).

The untreated aluminum side louvers can be anodized, powder coated, or painted to match the main body color. For further protection against road debris, the body is undercoated with a bed liner product (see Road, Sound and Heat Protection).

Street appearance is enhanced with various finish trims, grommets, and bezels (see Replicaparts, Ape, and FFR) including:

• roll bar grommets Photo
• shift chrome ring (included in 3.1 Complete Kit)
• upgraded side louvers (replaces pair in 3.1 Complete Kit)
• hand brake relocation to transmission tunnel and finish bezel Photo
• seat belt bezel Photo, Whitby $25
• steering column bezel Mike Everson, Norton MA ($35)

A metalizing process by Metal-Morphous can be used on interior hood and trunk pieces for an extraordinary vintage look. Photo at right shows a two-piece hood where the original scoop was replaced with a second piece (see Hood scoop discussion below and template) that is riveted in; see also this under-hood detail.

The original Cobra had a metal body with the hood scoop separately bolted on. The fiberglass FFR body molds the hood and scoop as a single piece. For a more precise period-correct look, a separate $80 fiberglass scoop FFR 12472 can be attached with buttonhead screws or rivets. An extension of the lower leading edge of the hood (that projects into the scoop) adds to the classic appearance. See also scoop top, bottom, an example of a fully riveted hood , and a detailed hood scoop rivet-placement template.

A more authentic look can be achieved by rolled edges around the cockpit, fenders, and body openings like the front nose, side louvers cutouts, and other body edges. This generally involves building up the body with filler and then sanding back to the original contours (see also the hood scoop discussion below). Careful finishing should widen the tail light mounting pads so that tail lights mount flush with the body.

Using hidden side body mounts, fabricated by welding bolt studs to an 1/8” steel plate which is then bonded to body with 3M HSRF, eliminates the “bolt-on” look of fiberglass shells. A more involved modification, called the dropped butt, lowers the rear body below the gas tank for a more classic appearance.

• sun visors (FFR 12042 $125), see photo at right
• the exhaust side pipes are loud (from 95 db idle to 120 db at high RPM) and get extremely hot; heat shields (about $250) make cockpit access easier and safer; the BreezeQuiet Side Pipe Kit baffles sound effectively
• a snapless tonneau cover (sourcing email wpdeal@gmail.com) for protection while parked can be attached to the side pipes
• for all-weather use, a soft or hard top (see new North Racecars LeMans top) can be added as well as a heater-defroster (FFR 14816 $320) and heated seats (∼ $175)
• rear wheel spat carbon fiber rock guards (FFR 12925 $60) protect against road pitting of the finished rear fender surface

A summary of build options lists costs and vendors for items discussed above as well as other planned modifications.