Pinto engine conversion

[40 Deluxe]

Originally Posted by Lannis

How are top ends in post 1988-cars lubed in this era of unleaded fuel?

Lannis

Usually the exhaust seats are induction hardened. There seems to be some kind of difference in the exhaust gas content of LP versus unleaded gasoline. In my career as a mechanic I saw a lot of LP engines with sunken exhaust seats, but very few gasoline engines. The exception being Dodge pickups with the Magnum 360 engine. I worked on a fleet of them at the AZ Hiway Dept. First we had the 1 tons that were used hard. The exhaust seats would recede to the point where the lifters were bottomed out and valves couldn't close. Soon the 3/4 tons started coming in with the same thing. After some more time and miles, the 1/2 tons started failing.