Gil,
Are you doing that with an early iron liner set of barrels or later SECAM (Nicasil) barrels? I have never flow tested either, but the 4 port barrels appear to have a lot more transfer port area and the ability to point the ports where you want them. In the US, only iron liner barrels were supplied with the early style crankcases that have a lot let area.
We found that single transfer ports can be opened up a long way but it's not easy to get the right port discharge angles as I am sure you already know.
Are you doing that with an early iron liner set of barrels or later SECAM (Nicasil) barrels? I have never flow tested either, but the 4 port barrels appear to have a lot more transfer port area and the ability to point the ports where you want them. In the US, only iron liner barrels were supplied with the early style crankcases that have a lot let area.
We found that single transfer ports can be opened up a long way but it's not easy to get the right port discharge angles as I am sure you already know.