Re: Tubular intake manifold design
If you're asking if anyone has ever turbo'd an inline four bike using a boosted single carb on a manifold...the answer is yes. Mr turbo and hann racecraft did em that way back in the old school bike turbo kit days and it's still done that way in some applications. Some with a plenum like box, and some with a tubular manifold like you're describing, however, the tubes come from a single box plenum chamber in all cases. Nowadays the plenum chanber sits atop the throttle bodies pressurizing the intakes in similar fashion.
There are some motorcycles (non turbo'd) which have a tubular manifold serving up more cylinders than it has carbs too, similar to the plenum x tubular described above. The Benelli six cylinder with four carbs comes to mind. This design can be a nightmare to tune though as the plenum gets excess fuel fogged into it from the 'reversion' from the other cylinders not on the intake stroke.
Anyway, I'm just babbeling here...what exactly is the question ?