There are differently configured 390 holleys. The 8007 is real good for use on 6 cyl. There is also a 6299 list which is better for 4 cyl apps. They are both configured different. May even be a few more made thru the years. That is why I asked about the list #.
I would put in the PV that is closer to the needed application. I doubt that any vacuum will be gained. Then the MJ can be tuned for correct cruise without the excess fuel from PV. Maybe start back to the stock jet size for a #8007 carb. If it runs good at cruise then start playing with the PVCR to gain fuel for getting on it. Tom
