TT has a good point. The TR6's were always essentially parallel port. That's one of the reasons that folks are after the earlier ones. The other is that the ports were smaller increasing charge velocity.
Before I get too far out of my depth here, there has to be some changes to the head, since it obviously isn't a TR6 head with two carbs on it.
Also, it's perfectly within the expectations from Triumph to make changes with some unexpected and unintentional benefits. Seen that before...
However, my statements with regard to the Bonnie heads stand. Angling the incoming charge away from the spark plug is a dumb idea, but that's exactly what Triumph did until the parallel port T140 head came out.
So, it's likely that welding up the existing head for single carb is much less of a good idea than just buying a single carb head. That's exactly what I'd do.
On a slightly different slant....I've been toying with the idea of getting a couple of Webco bolt on inlet stubs and running two carbs on my old Thunderbird. I would be after a bit more power, but I also believe that I could tune my motor to be smoother, which is something I like even more than the power.
PS Edit. I wrote my response before I read Stein's. We tend to think alike regarding these things. However, I would search old PeteR (rip) posts to see what he has to say about this subject. When he came on the scene years ago, most of us just sat back and listened. He was brilliant.
Last edited by HawaiianTiger; 07/15/19 9:35 pm.