[Plowman]

I've come into this thread a little late, but wanted to add a few of my thoughts.

I've run several 1850 carbs with both tunnel and x-ram intakes. I've found that street driving required me to restrict the liquid line in the metering block. Since the 600 carb was factory tuned to provide idle- we'll say for 8 cyl. in this case, multiple carbs will then be very rich at idle- beyond the adjustment of the idle mixture screws. With this done, the 1850's can be tuned with conventional methods to run very well on the street. I'm willing to discuss this more if anyone is interested.

As for the vacuum secondaries, needing to be changed I’ll have to disagree. Although tunnel ram does lower the engine vacuum, the secondaries operate off of venturi vacuum. They are completely tunable on tunnel ram. I also think they help in making a tunnel ram engine more streetable because they only open X amount from the venture signal. Mechanical secondaries can give too much CFM too easily.

I actually like the look of sideways mounted carbs. When/If you remove the jet plate and add a secondary metering block to an 1850 carb (to allow standard jet changes) you can no longer mount the carbs inline. Sideways mounting also helps with fuel slosh.

Plugs do tend to foul with multiple carbs due to fuel puddling in the intake, but a vintage MSD 7A will remedy that. I’m sure any hot ignition system today would work as well- I just like the old MSD 7 before they went to the 7AL.