1990 Mustang LX Drag-Car - Boss 340 Project

Our bumper cover has excess fiberglass that hangs over the Mustang's core support and must be trimmed back. Ty lays out a trim line using Scotch blue masking tape, which is preferred for such tasks because it does not leave residual adhesive when it is removed.

With the cover removed, Ty uses the Cengar air saw to cut away the extra material, being careful to follow his line that actually will mimic the contour of the core support quite nicely. The Cengar cutter is a high-dollar piece that Ty says is the ultimate tool for making detailed cuts in fiberglass, carbon fiber, aluminum, etc.

After cutting the bumper cover, Ty uses a block sander to smooth the trimmed area down into the masked trim line.

Since we're trying at all costs to keep things on the light side, we bolted Donathen Racing's super-trick, lightweight bumper-support bar ($110) to Boss 340's factory brackets, before sending the 'Stang to Raceskinz for bumper-cover fitment. Even though the bar probably will go unseen for most of its existence on the car, we totally dig the Black Chrome powdercoat finish, and highly recommend it to others who plan on installing one. Tim Donathen's chrome-moly bumper bars literally weigh near nothing, and are available for the front and rear ($200/set) of Fox ('79-'04) and SN-95/New Edge ('94-'04) Mustangs. We will also be installing Donathen Racing's tubular rear bumper bar/parachute-mount assembly ($325), when we get closer to finishing up the Boss 340 build.

Here is a backside view of the bumper cover, with the Donathen Racing tubular bumper bar in place. The bar is designed to fit in the same location as the factory bumper, and gives support for the bumper cover, as well as a more-than-considerable weight break.

Schoneck Composite's 4-inch to-the-windshield cowl hood ($795) complements Boss 340's new Outlaw LX front bumper cover. Similar to the cover, the hood requires trimming and we recommend doing it at the same time the bumper is being modified.

In addition to the front-end fitment, we decided to start knocking down the primer that has covered Boss 340's body panels since your tech editor acquired the Mustang years ago. Mike Smith uses a dual-action disc sander to handle this task, and will inspect the body for dents and imperfections that must be repaired before Raceskinz paint tech Rob Potts does his thing with the BASF paint we're using to give the Boss its color.

Sanding and cleaning away paint and primer exposes the imperfections in the body that were not really detectable before. Mike uses a Marks-a-Lot pen to highlight all of the problem areas, which will be repaired with body filler and then sanded and prepped for the fresh coat of primer the car will receive before it is painted. During this process we noticed the absence of four key pieces of molding (the body-band trim located just before and behind both doors). MPS Auto Salvage in Winder, Georgia, is the go-to outfit for hard-to-find Fox trim and other items, and Boss 340 definitely will benefit from MPS's deep inventory as it comes together.