I just put a 57 b intake and holley 390 cfm on my  55 with a stock 292 and A/T It had A intake with a 4v teapot before/ it sure rans alot better but I have a small stumble when I take off / so far I have check the float level,accelerator pump arm adj,move the pump cam to the #2 postion Im starting to think that maybe I need to replace the pump shooter which is a .25 but Im not sure which way to go. how can I tell if Im too rich or runing to lean? both can cause a stumble or do I need to change my pump cam? Also when my secondary open I feel a kick which I think is a flat spot I think a stiffer spring on the secondary will take care of that problem The cars has 20 lbs vac at idle, I have try runing the timing at 6 and 12 %  with total adv of 38% at 4k also the distributor was update a year ago and it also has a new fuel pump Im hope that someone has has had this same problem and can tell me what fix it

Joey! I had originally installed a PCV from mid 60s Ford 302 thinking engine size was close to 292.I ended up using one from a 4 cylinder 80 something Fairmont-Zephyr.If you take yours to an auto parts place you can compare orifice(air inlet) size and find one smaller than yours now.Size controls the amount of air and mine was getting too much air messing up the mixture.Hope this is helpful.

  

Thanks Mark. Yeah, this got me thinking not only about making sure about the PCV size not being too big, but also about location. Right now (with vented oil filler cap and later TBird valley pan with hole/baffle at the rear) , the PCV valve is tied at the other end into the port on the rear of my Demon carb. I have wondered for awhile now if that's been leaning out my A/F. So I blocked off both carb port and PCV line for a brief test run and I swear the darn thing ran stronger. I remember reading somewheres that as much as 3-5 cfm can flow through the PCV valve, so maybe I would be better off re-locating it off of the carb...? Demons like it rich, right? So would someplace on the intake manifold be better, located near to the carb so all cylinders get an equal effect? Then drill and tap?

Exactly where would the best location be, and do you think it's worth the trouble? Any and all opinions appreciated.

If there is a port on the carb for PCV it should be fine there-same as mine.If you found it ran better with the PCV unhooked(makes sense richer mixture) try either replacing the PCV with smaller(lower airflow) like I did or restrict it like Steve did.I found the PCV problem occuring at idle(inconsistent).At high vacuum(idle) the valve should be closed or very close to it working against the spring inside the PCV.Open too much or rattling like mine was gives inconsistent A/F mixture.I assume you blocked off the old road draft tube opening in the side of the block when you added PCV?

  

You assume right.

I get the concept of a closed system and the benefit of venting the oil cap straight from the filtered air from the air cleaner assembly. But I'm not worried about that right now, I don't put many miles on this engine.

I think I'll try a more restrictive PCV valve. Generally speaking I guess PCV valve sizes go roughly by displacement, but maybe I'll try something smaller. Mark, you mentioned about the 80s Fairmont/Zehpyr, you (or anyone) wouldn't happen to have a part number would you?

Just go by that application.80 Fairmont 4 cyl.Compare it with yours.Inlet size will be smaller and large end should be the same as yours now.