Anyone have experience with these? My engine setup will generate enough vacuum to boost the power brakes for a single pump, but the vacuum depletes quickly, and takes a minute to recoup the necessary vacuum to operate easily. It seems like a reasonable fix, especially if it give me an extra pump or two. An electric pump would be next but they are not cheap. Thanks in advance.

 

Just out of curiosity, what's your idle vacuum? Are you sure the booster isn't bad? I'm running about 12" to 13" and brakes work pretty well.