Lead or no lead?

[Sparkydave]

Many moons ago, I got dad some lead substitute for the Lincoln.  Looks like he didn't use very much of it, but it also hasn't been driven much since then.  What's the consensus on needing a lead substitute in the Lincoln V-12?

[Matt Harwood]

Skip it. There was very little lead in the fuel in the 1940s. It came into use in the 1950s as an octane booster when compression ratios started to go up. The stuff about cushioning the valves is bunk.

[Ray500]

It's more of a concern with the modern gas often having ethanol in it as that's alcohol!   Alcohol attracts moisture and that's a problem for any engine.  Costs more to buy it, but I prefer it and so the the ole V12!   I buy it at a Shell station as others continue to put ethanol into their gas as an extender and it's cheaper that way!  Only in recent times did the state government allow refiners to give motorists a choice, unfortunately most don't seem to care one way or another!   

[Lee H]

9 hours ago, Matt Harwood said:

Skip it. There was very little lead in the fuel in the 1940s. It came into use in the 1950s as an octane booster when compression ratios started to go up. The stuff about cushioning the valves is bunk.

Still, I would question why the manufacturers went to hardened valve seats in the early seventies when lead went away. I don’t think it was a cost savings measure.

 

I have always used some form of “lead substitute” in all my pre-unleaded cars. Cheap insurance, I guess. I do also believe that in low output, low valve spring pressure engines like the HV-12, it would take many, many miles to measure any difference in seat recession.

[Matt Harwood]

10 hours ago, Lee H said:

Still, I would question why the manufacturers went to hardened valve seats in the early seventies when lead went away. I don’t think it was a cost savings measure.

What else happened to cars in the early '70s that coincides with this?

[Sparkydave]

Thanks all, guess I won't sweat the lead substitute.

[Lee H]

12 hours ago, Matt Harwood said:

What else happened to cars in the early '70s that coincides with this?

I will assume your point is that leaner emissions tuning caused higher valve temperatures. While I can’t refute that, the “popular” conception in the contemporary press was that hardened valve seats were introduced to accommodate unleaded fuel. And there is at least some [easily available] evidence that the engineers believed that was the reason as well. See below.

 

I would be very interested in seeing any documentation that directly ties the introduction of hardened valve seats to  pollution control tuning. 

[19tom40]

The V-12 had hardened valve seats, so it doesn't require lead. In the 50's some manufacturers stopped using the hardened seats and depended on the lead to lubricate the seat. As far as I know selling fuel with lead for automobiles is against the law. It is still available at some airports for planes.