I have a Solex 34 pict 3 on the way thanks to eBay. I have no idea what jets are in it, I would assume whatever the stock VW has. Should I change them before even trying it? To what sizes?
Jet sizes will depend some on your intake set up. Plenum volume and runner inside diameter. I agree try the stock jets first. Might want to buy some micro drills to increase jetting if needed. Then once you know the sizes you want you can just buy the jets to fit.