440 heads on 383

[furious70]

Hmm, good to keep in mind. I might have serviceable 906s...... Don't know how far onto that road I care to go though. They'll need the valve seats hardened at the least.

maybe...heads that were run for years that still have good seats have a build up of lead that might keep them safe for years. If you're doing any machine work on them, then of course add hardened seats, but if they are runnable as is, the lack of the seats doesn't necessarily mean they'll fall aprt.

 

[Lieggi26]

maybe...heads that were run for years that still have good seats have a build up of lead that might keep them safe for years. If you're doing any machine work on them, then of course add hardened seats, but if they are runnable as is, the lack of the seats doesn't necessarily mean they'll fall aprt.

I will. Be replacing the seats and valves. And some machining done

 

[detmatt]

I will. Be replacing the seats and valves. And some machining done

A leak down test should be your next move.