Thanks for the replies. The Hot Rod test is really good info,(both parts 1&2).
I can post some pictures, but mine is the "Cross Ram" style with both carbs facing forward. Throttle linkage is on the drivers side of both carbs.
Most testing I have read about have the carbs inline or Max Wedge style with both carb primaries towards the middle of the intake.
The motor is a 383 with a 440 crank, 11 to 1 pistons, 296-557 MP cam. The heads are some old Stage 4s ported by ?, and flow 280 @ .550 lift.
After reading that Hot Rod article maybe I should put the old DP4B back on. My cam is closer to that Part 1 test than the cam in part 2.
There are so many variables that effect the outcome, but several years ago Chrysler Power Magazine tested B engine intakes and the TM6 was best. It did have some port work though where the plenum meets the runners, which makes a big improvement.