Saving Old Seagulls

Hello All

Bit of a random question, but does anyone know, or could possibly measure the diameter of the carb mounting stub on the cylinder of a forty plus engine?

Would it be the same diamter for a forty featherweight? I'm guessing yes as they share the same villers carb?

I need to do a little job relating to this and won't get to measure for a few days.

If anyone could help me, i'd really appreciate it.

Thanks

I just measured a couple and get .750" or 3/4" outside diameter. As far as I know there is no difference between a 40+ and a 40- block, I think this goes back as far as SJP/SJM. The difference in power is due to a different gearbox. The ones I measured where 60s and 70s motors?

Someone will correct me if I'm wrong on the blocks being the same.

Thank you for doing that for me.... Very kind

The century plus I have comes in slightly bigger at 7/8"

And the carby from the C100 fits and runs without any changes .... 40 cc to 100 cc ! Why is that ?