Hello again, it seems the more I do, the more questions I have. I'm replacing the cam in the 455 that I picked up a year ago. The original q jet needs a rebuild but I do have a holly 1850-3 600 cfm that I believe wold work as a temporary to break in the cam. I'm nervous about trying to rebuild the q jet, not having it correct, and not starting the engine quickly enough and destroying the cam. Would I need an adapter for the holley to the stock manifold. I plan on eventually putting the rebuilt q jet back on. I was thinking that this would be my best option for a quick start and correct break in. Any advice is extremely appreciated, thanks again, john
With the stock intake, yes, you will need an adapter. You wouldn't with an aftermarket aluminum intake. If you do get an aluminum intake in the future, always get the one with the Q-jet opening. It's easy to go to a Holley from the Q-jet opening, but not the other way around. https://www.ebay.com/i/231719658036...MIuM3yitOJ6QIVAYbICh025QEbEAQYBCABEgL9HvD_BwE
consider a 4 hole holley/qjet adapter also . a few more bucks but supposedly flows a little better . but I guess the 600's not gonna be on there too long anyway . there's a small ridge in the middle of the 4-hole from the casting I guess , maybe smooth that down also ? couldn't hurt .