P4120701 Small Block Mech Tach drive
Not recommended. Those springs are too short or too weak. The short ones will work for a while but will be overextended and lose tension sooner or later.
Try a primary spring from a Chrysler distributor - Halifaxhops is probably your best bet unless you have buddies with a stash of distributors or a local speed shop with a machine.
In a Chrysler and similar distributors, one spring controls the initial advance while the second spring engages only when the the advance has moved out several degrees. (see photo, secondary spring has a long loop)
You can also delay the initial advance by increasing the spring tension on the first spring. Bend the spring perch further out. Doing this the rate of the advance will not change, only the start. If this is drag race only, that's prob going to be fine. (in the photo, the primary spring perch is bent in to reduce initial tension)
In either case, with this distributor, you will still have to set timing at 2000 or 3000 rpm. Then see where the timing at 800-1000 rpm falls. The secondary spring's engagement point can be adjusted as needed. Having someone like Halifaxhops set it up using a distributor machine will save a lot of time and learning curve.
Not recommended. Those springs are too short or too weak. The short ones will work for a while but will be overextended and lose tension sooner or later.
Try a primary spring from a Chrysler distributor - Halifaxhops is probably your best bet unless you have buddies with a stash of distributors or a local speed shop with a machine.
In a Chrysler and similar distributors, one spring controls the initial advance while the second spring engages only when the the advance has moved out several degrees. (see photo, secondary spring has a long loop)
You can also delay the initial advance by increasing the spring tension on the first spring. Bend the spring perch further out. Doing this the rate of the advance will not change, only the start. If this is drag race only, that's prob going to be fine. (in the photo, the primary spring perch is bent in to reduce initial tension)
In either case, with this distributor, you will still have to set timing at 2000 or 3000 rpm. Then see where the timing at 800-1000 rpm falls. The secondary spring's engagement point can be adjusted as needed. Having someone like Halifaxhops set it up using a distributor machine will save a lot of time and learning curve.