need lead additive??

I don't think so. Flatheads have hardened valve seats and do not need the lubrication that the lead provides.
 
Yes I know Jack. But it's the only thing I might add for the valves. Should have clarified that, my fault.

Lead being a valve lubricant that is.


By the way Jack, I really like the color of your 39'. If you have more pictures of your car, I would be happy to see them.
 
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Does the introduction of valve rotators correspond with the removal of hardened valve seats? Methinks these two events are related.
Therefore, if rotating valve assemblies are designed to prolong valve /seat life, surely adding hardened valve seats in conjunction with the rotators must just about be the 'ultimate' set up for burning todays gasoline?
No such thing as overkill is there? Brian
 
Richard in Florida said:
Not entirely true. The late 8BAs had NO valve seat inserts; seats were cut right into the block. Good idea to add hardened exhaust seats next time you have it apart.
Click to expand...

I'm not sure what is considered a late block. My '50 Ford with the original block was built in 1st week of August of 1950 and it had no seat inserts for the intake valves. I had hardened seats put in all the ports, along with stainless valves
.
 
I discussed this issue with my machinist and the engine builder. Both claimed that 1) The additive is not necessary; and 2) the seats would harden over time. Since it isn't a race engine, no high compression and not subject to challenging conditions, running pump gas and not hardening the seats were ok.

True?

Dunno. So far, I've got 6,000 on one motor and 8,000 on the other and A-ok.
 
I think that Ford (in the Flathead years) always recommended that you use Amoco white gas, that was the equivalent of unleaded as I understand it. I've never used a lead additive in any of our Flatheads however I have installed Top Oilers (I use MMO in them) in both our '39 Zephyr and '39 Ford.
 
My 51 8BA has the stock Ford seats in the ex. and none in the intake. 49,000 miles and no problems yet, still runs great. I also add MMO to the gas tank ( sometimes I forget to add it, c.r.s.)
I have seen the later 8BA block with no seats.
 
On the "late" 8ba thing, it's generally known to be 52-3 (U.S.), though given Ford's rolling change habits there might be some late '51s.

For some it might be useful to understand the mechanism of exhaust valve errosion infrequently experienced with unleaded fuel. Basically the valve face tries to weld to the seat face (at the microscopic level). Then the weld is torn by the valve opening. The notion of "lubrication" from the lead is somewhat of a misnomer from the normal way folks think of lubrication. Anyone who is familiar with welding knows it's difficult to weld dirty work pieces. That's pretty much what the lead did, it deposited on the exhaust valve area/components and prevented the welding by contamination. BTW, since the tetraethyl lead is in solution before combustion it does nothing for the intake valve. Using logic, the trigger for welding is heat. Vehicles that experience exhaust valve errosion usually are ones that work hard (i.e. not normal driving). Examples would be heavy duty equipment, racing applications, and so on where high heat is generated/retained. Another experience of welders is the difficulty of welding dissimilar metals, thus the stainless valve/induction hardened seat/ and so on.

Another thing to consider, tetraethyl lead wasn't a common additive to gasolines until mid 1930s and beyond (in part geographically). So many old cars were in service new before lead was a factor in fuel composition.
 
Thats a very good explaination Uncle Bob. It should be pointed out that the "Lead substitutes" that are on the market are nothing but a sham. After a while they will build up a gummy gook in the carburator that plugs up fuel passages. Low Lead fuel for Aircraft is still available but only for Aircraft use, illeagle to be used in cars. Quite costly also.
 
Maybe overkill, but I add real TEL from Kemco in Utah to my 37 Tudor, 38 Coupe, 69 AMX, 70 Camaro, 72 El Camino and 74 Hornet.
 
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