Every old car and motorcycle forum has discussions on the topic of valve wear.

Controversial to say least especially as far a valve wear. Suspect the OP is concerned with area that this article addresses........Valve seat recession.

What valve reccession looks like:

http://holdenpaedia.oldholden.com/Valve_Seat_Recession
This engine was running on LPG.

http://automotivemachine.blogspot.com/2011/06/valve-failure-concerns.html


More info on the controversial topic:

http://chicagolandmgclub.com/techtips/general/540.html

https://oldschool.co.nz/index.php?/topic/20751-valve-seat-recession-explained/

https://www.jalopyjournal.com/forum/threads/unleaded-gas-vs-non-hardened-valve-seats.827920/

http://www.hotrod.com/articles/will-unleaded-gas-burn-exhaust-valves-in-muscle-car-engine/

While not being an additive fan.
Hardened valve seats during a valve job is one answer. Many believe it’s not needed ......that’s what makes it controversial. Under light duty use of a collector car plays a huge part in valve wear or lack of wear. Especially if your doing a complete valve job hardened seats install and never look back makes some sense.

Last edited by showkey; 05/03/2018 12:47 PM.