[mr0077]

With 2 x 390 cfm carbs mine ran best with both primaries synchronized (opening together), but with 2 x 600 cfm carbs it seems to be crisper off idle and at light acceleration with progressive linkage, where the primary opens, then secondary opens, both going WOT at same time). Seems like synchronized opening with the bigger carbs gives it a bit too much throttle area.