When you purchase Adjustable Camshaft Sprockets, you are expected to either purchase or provide cores to be modified.

 

You can:

 

-         purchase a set of sprockets, pay the core charge, and then have it refunded when you return your old cores.  You would buy both sprockets and cores from the web page

-         purchase a set of sprockets and cores outright (i.e. buy both sprockets and cores from the web page) and keep your old cores if you later intend to return the engine to stock

-         send a set of sprocket cores, and purchase a set of sprockets only (i.e. buy sprockets only from the web page).  If you purchase sprockets only from the web page without purchasing cores, we will wait until your cores arrive before shipping out the adjustable sprockets