ANSWER: For ths most part the Mallory distributors have the timing curve set correctly for your application right out of the box. Just install the distributor, set your initial timing, and you're good to go. But, there are going to certain applications where you will need to tweak the mechanical curve a bit. The need for these changes are based upon each individual engine's requirements. More information on ignition timing is here:
ANSWER: We have provided our customers with detailed assembly drawings so that you can see the various advance system styles. Use the link below to go to the distributor series assembly drawings. The main difference between the YT/YH and YL series is to look just below the brass sleeve the rotor slides onto. On the earlier "YL" series you will see a "Y-Clip" and a mounting screw that holds it in place. The "YT" or "YH" designs do NOT have this clip.
