Crane Cams 99600-1 - Crane Cams Adjustable Vacuum Advance

Now you can actually tailor your ignition system to meet a wide variety of driving conditions and requirements with these unique, easy-to-install adjustable vacuum advance kits. Comes complete with adjustable vacuum canister, featuring the unique adjustable vacuum diaphragm, three sets of advance weight springs, and a 3/32'' allen wrench, plus complete instructions.
The adjustability provided by these kits permits you to run the maximum ignition advance throughout the RPM range, without encountering detonation. Improved performance, efficiency and dependability are the major benefits obtained. Once the kit is installed, you can also quickly compensate for changes in fuel quality and altitude.