23 to 27 1 or 1½inch - but of course 27 will be slower when you injectI used a 25 X 1.5 for that. Never had any issues. I will say I've had some different oils that flow differently. When I've had thicker oils it's only meant I had to be more patient.
I'm a big baby though. I hate to go less than 25.
There are currently 0 members watching this topic