Whenever a brake upgrade is made, usually incorporating discs brakes at the front or even all around, most builders will upgrade to power-assisted brakes. The number of kits available in the aftermarket makes installing vacuum power boosted brakes relatively simple in any number of applications, but of course this does rely on the engine providing enough vacuum to operate the booster. Using a high-performance motor, high-lift camshaft, or a supercharger can see vacuum levels that are marginal or insufficient to operate a vacuum booster, though using dual diaphragm or large diameter boosters can help.
While the Smeding 383 stroker small-block Chevy destined for our project '49 Chevy will provide enough vacuum for a booster, I also wanted to run the brake master cylinder under the floor, rather than on the firewall, and as the car will sit pretty low, I was concerned about a brake booster hanging down under the car. When I saw ABS Power Brake's Electric High Power master cylinder, and more specifically its compact size and the fact that it could be supplied with a bolt-in bracket to fit the '49 Chevy, it seemed like a no-brainer. ABS actually offers two different brackets, one for '47-51 cars and another longer version to fit '52-54 Chevy cars. Check their website for other applications as they can cover way more than just these models. The master cylinder itself (that is, without the bracket) measures just 10 inches long and 3 inches tall, and can be mounted on the firewall or on the frame, either remote fill or with attached reservoir, though add a couple more inches to the height if you opt for the non-remote fill versions. Whichever option you take, all are polished aluminum and there's a choice of styles if you go for the attached reservoir models.
An advantage of the electric system over a regular vacuum booster is that whereas if the engine cuts out with a vacuum booster you lose the power brakes and the pedal is very hard, if the power is lost to the electric version, you will still have at least 20 full power pedal pushes thanks to the accumulator in the system, and even then it will simply revert to regular non-assisted braking without the "hard pedal". Sounds like a win-win situation right? I thought so, so I trucked the Chevy over to ABS and followed along as Pedro installed the system in an afternoon. Now I just have to plumb the remainder of the system--yes we'll show you the correct way to go about that pleasurable job shortly--and very soon the Purple Pig will have both "go" and "whoa" again.
