I run 3oz per gallon of Pennzoil full synthetic in my motors.
I still have 9 gallons so I’m good for a couple years.
Most all my motors are bushing motors including this
1939 Fleetwin, Bushing – Crankshaft Rotary Valve , Model 4335.
Why is there detergent oil today? This is why?
The junk non-detergent of the past is the reason these
rings were stuck (video) and the motor was full of carbon.
4 stroke crankcase oil is not meant to be mixed with
gasoline. Two cycle oil is. Running a heaver oil than you
need only creates more friction shortening the life of a motor.
https://www.youtube.com/watch?v=KjSPM6mp4eY
A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.