Torque plate valve job

[Pablo]

Has anyone ever compared valve seal with a torque plate (or block) to doing it without a torque plate? Spark plug in or out?

Been doing some reading and have found that at least some ford heads will deflect enough when torqued to cause valve leakage. I was wondering if our heads might have a similar issue.

 

[bison]

Has anyone ever compared valve seal with a torque plate (or block) to doing it without a torque plate? Spark plug in or out?

Been doing some reading and have found that at least some ford heads will deflect enough when torqued to cause valve leakage. I was wondering if our heads might have a similar issue.

I'd believe there is some deflection but there is no way to duplicate what is going on at25psi/6000 rpm. So it's like chasing after pennies when you should go after $. You could have a lot of leakage and not lose hp. Think about how much leakage you are getting past the rings. Reducing leakage there does little. Reduces blow by but does not increase power.

 

[Pablo]

Yeah that is true but wouldn't it make sense to reduce the variables? If you are getting out of round at full boost and you were out of round to start with it could stack up to be substantial.
I would think an exh. valve leak wouldn't be such a huge deal from a power standpoint but an intake valve? That sounds like it could kill some power. Maybe it wouldn't. I read about one application where just loosening one of the head bolts reduced leak down by 10% through the valve.