Fully adjustable centrifugal advance and, you can adjust how much advance you have, AND how fast (and when) it comes it by loosening the centrifugal stops held in place with an Allen setscrew.

Centrifugal timing is adjustable between 16-32 crank degrees. The spring kit gives you 14 different advance curves, for a LOT of tunability. Each of these can be further tuned by slightly bending the centrifugal spring mounting tab (this loosens or tightens the spring a little, and advances or retards the advance curve by up to 300 RPM from the spring's setting).

We prefer to set it at about 8 degrees initial (too much means tough starting when the engine is hot), and have the centrifugal advance limited so it totals 28 degrees (36 for Semi-hemi engines), set up so the advance comes in sooner than the 009. The faster initial advance WILL give a crisper throttle (many race cars run LOCKED 30-32 degrees, for example) and more power from idle-3000, with less/no hesitation.

This is one of the last OEM N.O.S. units we have. There's a bit of galvonic dusting on the exterior of the Distributor body but, this should clean up nicely. Look at all the illustrations/photos for details.