Lancia Flavia Coupe 2000 - hardened valve seats

[lancialulu]

Who has reported valve damage on this forum since unleaded became defacto. Tim Burrett is an excellent engineer but I suspect that the problems were occuring before unleaded anyway (do we remember our parents cars with burnt valves??). Anyway for modest use it is not going to be a worry so long as the engine is to a good standard. But for GT use one should ascertain the quality of the valve seats. I recently presented my Sport 1600 cylinder head (it had done 110,000 miles) to my engine shop to replace the valve guides (well worn), and to re cut the seats (nothing wrong with them) as you have to when replacing the guides and my shop said they have never seen such hard material and complained it was ruining their cutters...

[neil-yaj396]

I think you are right Tim. Valve seat degradation post leaded petrol was mainly limited to the cast iron heads of old British cars, even then I ran my Frogeye Sprite for several years on unleaded with the odd squirt of Redex with no issues. Our cars generally don't do the mileage for this to raise it's head even if it was an issue in the first place.

[fay66]

I've been running my 2c Berlina on straight unleaded fuel without any additive for at least 15 years and 25.000+ miles with no problems.
Brian
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