Oil return line

Hey bill

We installed the 2nd return line . Crank pressure goes to 5 lbs max at 200 f 5100 rpm. Then down to 1 at 1900. Is there any minimum to worry about?

The primary issue with dual returns is that the Oil will pool over the lower return with all the gasses returning unobstructed through the upper return.
Once the pool gets deep enough to cover the upper return and the pressure raises the Oil will then return through Both lines.
This is not necessarily terrible as the same thing happens with a single return, nose down on approach.
The Oil level will vary and transfer between the tank and the sump as the pitch attitude varies.

1psi just indicates that most of the gasses are returning in one hose and most of the oil is returning through the other.
If this is a Tail Dragger, the effect may be significant.
As long as the Oil Pressure is stable you should be OK! 

Do you have a 915 style Oil Tank, with dual return ports?
How did you plumb this?

We made a fitting to utilize the port for the turbo return.

oil pressure actually seems better but I will monitor it. It is a trigear and there was oil in the front plug .i plan to fly it tonight.

 Thanks for your input. We’ll pull the odd cylinder this winter to check it . Maybe a poor break in?