Optimax leak down test

[MH401]

I'm going to perform a leak down on my 200hp optimax that I found 3 chipped reeds on, what is the proper psi to put into the cyclinders?
Also I'm assuming I'm going to have to hold the flywheel/crank with some sort of breaker bar so the motor won't rotate?
Just looking for any tips to perform the test accurately
thanks

[thomasfouraker]

Even at 50psi it can be hard to hold and dangerous. Ideally 100psi with a locking mechanism on the flywheel woul yield 1%leakdown per psi lost.

If at 50psi, each psi would indicate 2%leakdown.

Have you you looked into piston stops that thread into the cylinder head spark plug hole? You could use a few of these in adjacent cylinders to keep the motor from turning over while you are testing another cylinder.