I currently have a 1977 Mustang II with a 302 - Automatic Trans - with a 4bbl vaccuum secondary carb. The carb is a Holley 600 cfm. I need that carb to open quicker on the four. I see the manual indicates changing the spring in the vaccuum chamber... will this work? The timing is set perfect, running dual straight 2-3/4 pipes to the axle with Flowmaster mufflers. The car is breathing but I'd like to shred the tires on the shift points with the equipment I currently have. Any tips or tweeks are welcome. Thank You in advance.