Do I need a lead replacement additive?

[Jetrebel]

Newbie here, the car in question is a MM (1949)

Do I need a lead replacement additive? There is some of those Spitfire balls in the tank that is supposed to do the same but from what I’ve read they probably don’t do what it says on the tin…

Thanks
Jason

[geoberni]

Hi Jason
Welcome.
You're correct, all the solid things you put in the tank that claim to be a 'one time remedy' are just one big confidence trick.

If your car has the original engine still, I'll leave confirmation to someone who also has a side-valve, but IMHO, for any A Series engine the answer is that you shouldn't worry about it unless doing high mileage.
There are people who swear by additives, but additives are a bit of a Marmite thing, some love them some don't.


See this as an example of past discussions viewtopic.php?t=70508

It's like the question of Ethanol in fuel.
In the 1920s, when they were looking for 'anti-knock' additives, Ethanol was there alongside Lead as an octane enhancer.
The industry went towards Lead, now we gave up lead, it's swung to Ethanol, which of course also has other environmental advantages.

[svenedin]

I do use the Castrol Valvemaster. I cannot say whether this is strictly necessary but I bought a case of it a while back for a cheap price. ESM use that additive too.

It’s important to regularly check the valve clearances. I did try the bigger gap (15 thou) but the engine was too noisy for my liking so I use standard clearance.

Stephen

[Monty-4]

There is a whole book on the subject that has been recommended on the forum before if you fancy delving deep!

From memory; without any other changes modern (lead-free) fuels will tend to vary more in their burn times from cycle to cycle ("cyclic variability") than the old fuel, causing the engine to run hotter as if the ignition was too far retarded. This is why hardened valve seats can be a good idea especially if doing loads of miles at higher speed. Ethanol blended fuels actually help the variability at low (read: normal, not racing) RPM ranges.

For a standard A-Series I'd agree and say the expense isn't an essential one. Make sure the cooling system is performing well, your rubber hoses are E10+ grade, never let any water get into the fuel system as this will cause rapid corrosion inside and for E10 you may richen the mixture a bit (more oxygen in ethanol, so leaner) and advance the ignition slightly.