Just did a complete PM on it, added some right thrust, and while I had it on the floor happened to look at it from directly behind and think I found the problem. It had a very slight left rudder at neutral. Considering how rudder sensitive this plane is, I can roll the plane with just rudder, that might be all it is. I also found the reason it rolls left on take off, the left aileron is just a hair higher than the right one. At anything above takeoff speed it tracks straight, so not going to touch it just yet, first want to see if a touch right trim on the rudder and added right thrust is enough to get it tracking straight now. The rudder was off by 1 mm, and considering how much I had to drop the elevator on my cub to trim it, 5mm, this might just be the key.

Now hoping the engine stays running more than a few minutes, I replaced the clunk line in the tank, it looks like it stiffened up too much and did not move at all when I move the plane around, Last year it ran really good, but this year it hasn't run for more than a few minutes once airborne.

I picked up a 2D/3D inertial stabilizer last week and mounted it, will give it a whirl to see what it can do. If it helps keep the plane stable, and the rudder tweak fixed my taking off, then I will put it in my P-51, and hope it corrects its nasty snapping tendency. Pretty sure I found the cause, and wont need it in this plane, once it is off the ground it handles like a dream and is a blast to fly. Also a lot of fun to watch it come in sideways in a cross wind for landing.