Re-tighten nuts after exhaust gasket change?

[azevedoflyer]

Guys/Galls:
My engine is a O-320 A2B.
Is it necessary to re-tighten exhaust nuts after changing exhaust gasket seals and running the engine?
I just changed the old, leaky ones by Lycoming original part. They look rather flimsy as if designed to fail in a short time.
Is there something better, more robust out there?
Nuts tightened with 10 ft.lbf, a number I found hand written in my maintenance notes. But I am sure I was not the one whot wrote it.
Is this the recommended torque?
Thanks,
Miguel
N8714D

[Steve Pierce]

According to Lycoming Service Instruction 1204C when using beaded exhaust flange gaskets after initial installation, retorque the exhaust flange nuts after the first 25-hours of engine operation to allow for proper seating of the beads. There is no mention of retorqueing the spiral wound type gaskets.