My engine is a 1986 13B with 88 hrs since remanufacture.
I fly a Zenair Zenith with a cogbelt PSRU and a Warp Drive 3-blades prop
and  this engine never runs above 5700 rpm
When I installed this engine in my Zenith I removed the metering oil
pump and have been using two stroke injection oil mixed in the
automobile  fuel  ( 87 octane gasoline)
At first I used a volume mix of 128:1 gas to oil and soon noticed an
increase of engine lubricating oil volume in the oil pan
I have gradually reduced the volume mix of gas to oil to 140:1 but there
is still a slight increase of engine lubricating oil in the pan.
Also a local mechanic has mentionned that the two stroke injection oil
is degrading the 20W-50 engine oil.
How much can I reduce the volume mix of gas to oil ?
Please advise
Yvon