Originally Posted by
Swiley383
I have read vacuum secondary on a tunnel ram won't work right due to low vacuum. Contact Holley or Quick Fuel or some other carb manufacturer and see what they say.
Not true. Manifold vacuum has nothing to do with vacuum secondary. In fact it is recomended you use VS carb on your setup. BTW: 1850 holley is a 600 cfm carb.