I have a 1964 Ford F-250 truck and pulled the 2100 and intake off, installed a 57 T-Bird "modern" Holley-flanged cast intake, a 1" solid aluminum 4-hole PCV ported spacer and a rebuilt 4100 4V off a 66 Mustang, 480cfm converted for manual choke using the 2100 parts.  The truck has factory PCV system.  So I re-used the original PCV valve with the threads pointing to the carb spacer.  I read elsewhere that the original 2 barrel PCV flows too much and can create a high idle.  I cannot get the truck to idle below 1500rpms.  Do you think the PCV is the culprit?  What PCV is recommended in this application?  Any potential gotchas for vacuum leaks for this conversion?

Another note is I have a new aftermarket power brake/dual master cylinder set up where I spliced the vacuum line for the booster between the carb spacer and the PCV.
Thanks,
Mike

PS, I tried to figure a way to edit the the title as it got hosed up......sorry.

I would isolate the PCV and the booster one at a time to see if either one helped. If you plug both of them off and it still idles high, you know you have other problems.

I will give this a try this weekend.  

Has anyone tried using the Borg Warner PCV 280 in-line valve with the conversion to the 4100?  Kinda hard to know which PCV would work when you start to change things.  Guessing the original V100 may flow too much with the 4100 with 1.08 venturies.

The fellows are right - put the vacuum line to the brake booster on its own line. You have a "vacuum leak" - hopefully its just the PCV. When faced with a PVC based leak - I usually just throttle the hose with an orifice - electrical butt splices work nicely and they can be crimped a bit if you need to.


If you look at the port where the PVC was screwed into the original manifold - the manifold has the smaller orifices for the two sides of the manifold drilled into the iron manifold.  


 
 Steve Metzger       Tucson, Arizona

It was a vacuum leak....nearly 40 years working on cars and I did a rookie error.  I thought the port on the back of the manifold wasn't opened up....it didn't look drilled through....it was.  Sighhhh!  I put the booster on that port and eliminated the T fitting off the spacer plate thereby plumbing the PCV directly to the spacer plate.  I still might try a different PCV but the idle is around 750-800 rpm with a slight roll to it so it might need to be restricted a bit.  I'm using the solid plate shown at top of picture.  I had trouble sealing the small block Ford hollow plate.

So I think I will try using this PCV since I already have it and use this hose to adapt.  It's a Dorman 47128 PCV hose with 1/2" on one end and 3/8" on the other.

Re the carb base sealing problem. On a "B" intake some base gaskets like the Mr Gasket 55 have 1-3/4" holes which are very marginal on sealing on that intake. However, there are gaskets like Interface 8092 or Armstrong VB 72 which have 1-5/8 to 1-11/16"  holes that fit better. They are the ones our Moderator Ted uses for that intake..    


Paul

have a 49 merc pickup with a 292 4vmanifold holley 550 cfm. use the intak hole you show for brakes. plumded the pct into the air cleaner,carb side of dry air cleaner. as well made a metal plate that goes manifold then carb,made sure spacer is large enough so carb to spacer has good seal. my truck will now idel 600 rpm . i also have power brakes disc front drum rear.

I can't find a front disk kit for the F-250.  Sighhhhhh!  I'm hoping to install the new inline PCV this weekend but got sick.