You should be able to adjust the secondary opening point, not sure on your Holley, but it should either be by bending the linkage arm from the primaries to the secondaries or by an adjustment. Mechanical secondaries are usually a bit much on the street, I much prefer the vaccuum secondaries, then adjust the opening point and rate by changing the spring in the vaccuum chamber for the secondaries. Might want to invest $20.00 in one of the many good "How to tune your Holley" books that are available.