[CompClassics]

It is Vacuum assisted. The unit I used (photo) is probably 2/3 the size of the Lockheed unit. I had forgot to mention that the brake booster was installed in the front brake circuit in my application. You can install another unit for the rear brakes if you feel you need more brake effort but the one worked perfectly in this application. This particular unit is less than 12” in length and the vacuum chamber is approximately 6” diameter. Please feel free to email me for more info, jkb5@sbcglobal dot net