On another thread dealing with oil use and leaks in Ford flatheads there was mention of adding a pcv to them. Anyone have pictures of how you did this on yours. No sense in reinventing the wheel if someone has come up with a simple solution.
if you have the later flathead 49-53 there is a guy on ebay selling a kit for $30,i intalled his on my 8BA and works great...just put flathead pcv in search ,will not work with early flatheads...
Today I removed the road draft tube (under the alternator at front of intake manifold, can't see in picture), shoved a PCV valve in the hole and ran a 3/8 hose into the fitting between the two back driver's side cylinders. Cool, or am I leaning out those two pots?
Since my '32 Ford 4 door was running a electric fuel pump the PVC value was used in the back of the intake. HRP
I put a modern filter on top of the fuel pump stand tube for the air intake. I put a PVC in a drilled hole in the front of the intake and ran a hose to a drilled port under the carb. I blocked off the original 59A draft tube with a freeze plug.
In '49-'53 engines, remove draft tube and replace with a 1" rubber plug with a hole in the center. Insert PCV valve from a similar sized engine in hole of rubber plug. Run rubber hose to manifold vacuum port. Done.
It may be safer to drill and tap under the carb so you don't lean those two cylinders and draw from all eight.
usually the pcv hose is connected to the carb vacuum for pcv or base of carb to reduce lean out. putting it between cyl may lean them out. RB
It is effectively a small air inlet affecting mixture. You are tapped into both sides of the manifold there, but I would suggest a central location so all cylinders are affected the same for any tuning needed rather than affecting 2 cylinders only. On some stock manifolds there is 3/8 pipe hole behind carb (with a plug in it on most vehicles) for heavy truck brakes...on others there is a flat spot for it to drill. This hole is shallow and leads to 2 small holes into area under each side of carb...perfect. A few hotrod manifolds have enough meat below a primary carb to drill, again easy way would be a shallow hole for a tube adapter and 2 small holes exending that. Many people on here have drilled into the 2 sides of manifold UNDERNEATH, hanging the pcv down into valley, oft with a length of hose leading into the front ventilation stack... not convenient but neat, and how often do you want to see the thing? Ford put PCV's on many wartime engines thus: Adapter under carb drilled into both barrels, pcv below carb with hose to right side of the cast area where generator bracket is. This puts the inlet right above that vertical stack inside, just right for the system. The small draft hole at RY of pan is simply blocked...original PCV pans were simply not punched there. The early engines with PCV also got a much better aircleaner to replace the little brillo pad filter that was stock. Remember the path...air is meant to go into engine via the breather, at back on early, up front on 8BA. Air gets sucked through engine, then is removed through the pcv from the area of that front vent stack.
Well yesterday turned into a long day. I took everyone's advice not to use the vacuum port by the two cylinders. I pulled the intake manifold to drill a PCV hole. This is a V8-60 with a 97 on the stock manifold, so while I had it off I decided to bore the manifold from 81 size ports to match the 97. Well there wasn't enough meat and I cut through into the heat riser area that surrounds the ports under the carb, on the back side only. So, I filled that side of the heat riser area with epoxy and finish sanded the ports. Now, filled with epoxy, I figured I might as well drill from the outside, through the epoxy, into the two intake ports about and inch under the carb flange, for the PCV port. Time to put the manifold back on, I decided to block the two heat riser ports at the head with thin gauge stainless steel under the gasket. I cold have left it open, with the front half of the area in the manifold still open, but was worried about the epoxy melting. What am I giving up by blocking the ports? No heat riser in my exhaust manifolds. Hopefully it holds up long enough until some kind sole offers me a couple of 81 for the 2x2 manifold I have. It should run a little better, there was a pretty good step between the 97 and the stock ports.
You have an aluminum manifold and you live in California...so most likely you don't need to worry about warmup at 30 below. Without severe winter weather an aluminum manifold will generally get warm enough pretty quickly without its heater.
Thanks Bruce. Yes, 40°F is probably the lowest I'll ever be driving in but I do plan to drive my wife to work in it (she may have other ideas..), a 2 mile trip so it won't be getting very warm then. But looking at aftermarket flathead intakes, many don't even have heated areas.
There are two of those, between the front and rear paired ports and joined by grooves into the ports. They feed vac from both sides of manifold to distributor brake and to wipers.
That's how mine is, and actually the hole and slot looked too small for PCV. The difference between using it for distributor or wipers and PCV is with the PCV you have a continuous stream of air coming in. Whether it would be enough to lean out those two cylinders or not I don't know.
PCV isn't continuous. That's why there's a special valve used and not just an open port. Ideally, PCV flows at medium vacuum conditions (cruising). It should close at high and low vacuum conditions (idle and WOT). This is why the valve needs to be sized to a particular engine, so it behaves as it should, otherwise it's just another vacuum leak.
They are never fully closed, even at idle. But it's the time they are most open (cruising) that would worry me.
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