Technical Flathead ford valve stem seal question

I am finally getting back into my 41 Ford build. About a year and a half ago I picked up a rebuilt 221. I installed my isky cam and removed valve assemblies to swap the original springs with a new set of isky springs. There are no valve stem seals on the intake valves. EVERYTHING is new, valves, springs, guides, etc... It has the early mushroom valve tips and split guides.

My questions are, how much oil should I expect to burn with the old set up? None? 1 Quart every 100, 200, 500 miles?
Did these stock motors smoke a lot because of no seals? If so, just a puff or 007 smoke screen?
If they burn a decent amount of oil, how are the plugs effected from the oil? Lots of fouling or not even enough to matter?

Considering everything is new, I really don't want to spend money on upgraded parts if its not too bad.

 

To help eliminate any oiling issues you should not use the split guides and mushroom valves. The best combination is the 8BA type one piece guides and related valves the valve guides have a grove around the outer diameter so a seal can be used this greatly helps unlike the two piece guide that has no sealing provision at all. Flathead Ford V-8's never had valve stem seals but when you use new guides and valves the tight clearance helps eliminate oil issues.

 

I am far from a flathead expert but the 59ab flathead we rebuilt for my car used NOS mushroom valves and seats and I must say it hasn't used any oil. Although I don't run my car on the road yet, I have run it fairly hard off road a few times in the last few months and it hasn't used any oil, the plugs are clean, and it doesn't smoke. Putting it together with NOS stuff was the ticket I believe, it really took the guess work out of assembling the valves. We just put it together and ran it. The only oil the engine uses is a few drips from the bell housing after it gets warmed up


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I don't fit the guide seals when I build a flathead, there is almost no oil getting between the guide and block, trust me. I've carefully inspected this on a few motors I've built , after run in and after many miles, and there is no wetness or buildup of oil above the seal groove at all. Suggesting no oil flow into the ports. The seals seem to break down and stick the guides in like glue when I have used them, makes future disassembly a complete bitch.. So I say leave them out. Run a PCV if you are concerned, this will reduce oil mist in the valley area somewhat.


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Hard for oil to run uphill...... just saying.

 

Oil could get sucked up the intake valve guide. The seals only go on the one piece 8BA intake guide on the outside , like a square shouldered o ring. Exhaust seal are of little use as they get cooked. As said a good guide and valve rarely loose oil. A little stops them sticking.

 

If you have ever tried removing flathead guides, you'll know nothing is getting by them.

 

Do note in the replies above people are discussing TWO ENTIRELY DIFFERENT seals.
Stock flatheads have a big seal in a groove around the intake valve GUIDES to prevent vacuum from pulling oil past OUTSIDE of guide and burning it. Good idea, new ones will be cheaper than the postage to deliver them, probably useful but this area will seal itself pretty rapidly in use anyway.
Flatheads have NO seal for where valve goes through INSIDE of guide. This is generally not a problem in use if all the baffles in valley are in place and things are not worn out. Split guides are probably inferior to one piece in 2 or 3 ways I can think of, but do not actually make noticeable trouble. If you have new stuff there don't worry about'em.
On the sealage...remember the once-popular small block Chevy, used on may rods before the flathead was rediscovered? I seem to remember that for about the first 20 years they used no seals. They used a simple umbrella...and an o-ring to keep oil from running down from the keepers. Why the umbrella and ring on the Chevy but not on the FH??? The Chevy, if you recall, had its valves installed upside down so oil could just run in there! Ford made gravity his friend. Chevy tried to fight it...

 

Hence my reply.... hard for oil to run uphill ..... LOL

 

Now for the smartass answer: "The only Flathead VALVE-SEALS we ever worried about were to make sure we lapped them in properly"!! "If you'da needed them, Henry woud'da put 'em there"!!

 

Your original post states you have no seals on the intake valves. Intake valves should have seals...no seals on the exhaust side.

 

Thanks for the replies. The flathead valve seals I knew of were the ones that went on the outside of the later one piece valve guides, as stated above. I thought they were standard on later motors but I wasn't sure. Sounds like I should be just fine with the original split guides.