My AZU 250 is fitted with a 602 engine. I have no idea who did it: it was done long before I bought it 15 years ago. The van is an ex-Post Office one - yellow paint everywhere under the current colour (grey)

The 602 engine however is fitted with a single choke carb, a 34 PICS 10, probably because that way whoever changed the engine didn't have to alter the push-rod between the accelerator pedal (the one hinged on the cab floor) and the carb.

Would it benefit from a slightly larger main jet? the one fitted is either a 155 or 165 - the middle number is difficult to read, but I think it's a 165.

I'd appreciate advice.

I drove a single carb on my 2CV for years,it was economical on fuel but dont remember what jet i had

It seems like a "try an error" approach ιis your best bet.

http://www.2cvstuff.com/Files/2CV/108161/8161CH03.pdf

With some jet info at the end.

In the end I fitted a 170 jet, and I'd say there was some improvement to the van's performance. Of course, "van" and "performance" are two words you don't often hear together.

There's a hill which previously needed 3rd gear which can now be done in top. I don't think that's very scientific, but the performance is certainly no worse.

I probably should have said that I am also using 123 electronic ignition, and that is probably optimised for the twin-choke carb.

i had the 34 pics 6 in till recently and the car did run very well. But it got worn out. Now i have a 34 pics 10. Car runs well but it isn't perfect yet, will need some more adjusting.. it seems to have some 2cv4 jets in. with the old one the car did climb very good. In fourth gear the steep hills near the Spa racing circuit. i have 123 too.