The days of transplanting huge old Camaro boosters onto a ’40s/’50s truck firewall are—for the most part—far behind us. Typically, behind that massive air canister is the same donor car’s pedal assembly and, just as likely, its tilt column … all of which is completely unnecessary in this day and age.
Classic Performance Products has developed an all-new firewall-mount brake booster/underdash pedal assembly—an all-in-one, compact, simple-to-install unit that’s designed specifically for your 1947-1953 Chevy. Other than the mounting/pushrod holes on the firewall, there’s no modifying whatsoever to make the bracket, or its counterpart components, do exactly what it’s designed to do: fit.
The underdash bracket incorporates an ergonomically shaped swing pedal (versus the stock pedal that requires cardio workouts to manipulate) with adjustable brake light switch and its rearmost (dash) mounting points piggyback with the factory column drop. The opposite end sandwiches the firewall sheetmetal and the exterior-mounted booster and master cylinder assembly. Simple as that.
We’ll illustrate the simplicity of the product with the following install on a 1949 Chevy 3100. Bear in mind, though, this particular truck had already been stripped down to a bare cab: no gauges, steering column/box, or stock pedal assembly to remove, so much of the dirty work is already behind us. Fortunately, none of that is imperative to the task at hand, and it will allow a much better visual perspective of the installation procedure.
Image may be NSFW. Clik here to view.01 The bracket slides up, underneath the dash as one whole unit—no disassembly required.
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Image may be NSFW. Clik here to view.02-03 With the truck’s original column and frame-mount pedal assembly already removed, the stock cast-iron column drop is retained to facilitate mounting the new booster bracket to the dash. (For mounting only, shorter bolts can be used instead—this simply emulates the integration of the stock steering column/drop.) Flanged nuts are supplied with the kit.Image may be NSFW. Clik here to view.04 The bracket will have some flexibility as far as exactly where the booster flange aligns on the firewall—this will allow you to position it precisely where it needs to be before drilling the mounting/access holes.Image may be NSFW. Clik here to view.05 To be more accurate, we laid out blue tape behind the flange to mark the sequence of holes—we started with left-side center …Image may be NSFW. Clik here to view.06 … then removed the bracket and plotted our layout using a level to ensure everything was straight.Image may be NSFW. Clik here to view.07 The bracket was then reinstalled and aligned with the “leveled” centerline; both slotted master cylinder holes marked accordingly (Note: these two holes are only used for manual/non-power booster applications … we won’t be drilling them).
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Image may be NSFW. Clik here to view.08-09 With the bracket located off the centerline/MC hole template, we first drilled the lower right mounting hole; a nut and bolt were used to secure the bracket in place while the remaining holes were marked and drilled.
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Image may be NSFW. Clik here to view.10-11 Once the perimeter bracket holes were plotted and drilled, the booster pushrod center hole is made with a 1-1/8-inch holesaw—it can be piloted from the interior, then finished from the exterior firewall side, or drilled out completely from under the dash.Image may be NSFW. Clik here to view.12 The bracket is temporarily bolted back onto the firewall to verify hole placement (just in case), and any sharp edges deburred.Image may be NSFW. Clik here to view.13 Now the brake booster assembly, with the pushrod clevis threaded onto the booster, can be installed through the firewall.Image may be NSFW. Clik here to view.14 As with the dashboard mounting ears, the booster is fastened with supplied flanged nuts. The pedal is set so that there is no preload on the master by adjusting the pushrod clevis accordingly. The brake light switch can be set once that has been done as well.Image may be NSFW. Clik here to view.15 The 4753FBB4 8-inch booster kit is set up with an internal combination valve for four-wheel disc brakes—so no additional means of metering/proportioning are required … simply plumb the valve directly to the perspective caliper flex hoses.Image may be NSFW. Clik here to view.16 Bracket install complete—almost. After the supplied billet pedal pad is bolted to the brake pedal and set to the driver’s liking …Image may be NSFW. Clik here to view.17 … we installed a new CPP tilt column to ensure a complete package fit. Stay tuned for the full steering component installation!00
