I posted this up on a motorcycle site im on...figured id post here and see what you guys would say.

 

What I am wanting to do is build a pair of intake manifolds to run a pair of typical motorcycle carbs. The advice I need is what size and what kind of carb would you recommend?

A guy who was running this engine in his VW beetle ran a pair of 40mm downdraft carbs

Right now I am considering a pair of 36/38/40 Mikuni Roundslides, Factory Harley 40mmCV carbs, and a set of factory XS650 38mm CVs.

Do you guys have any other recommendations?

I've Posted this Pic in Other Thread:

 

 

About Dual Carb Setups: in Australia were Available a "Safari" Version of EA81 Subarus...

 

 

 

 

 

 

I Believe that since Water passes Thru the intake Manyfold, a Pair of independent intakes Wouldn't Work Well

a water passage can be made to bridge the block with a hose or pipe, if some clever welding or engineering was designed into the custom setup

this guy just had a tube in each flange and they were connected to each other.

 

 

thats all the coolant does right? the manifold just serves to pass the coolant from one side to the other?

the hot coolant in the manifold also helps with the fuel vaporization and stops the intakes freezing up in cooler temps.

i made a stainless intake manifold to suit a weber 32/36 a few years back for a EA81 aircraft engine....the owner of the aircraft wanted the water piped seperately.

 

intake ice problems quickly showed up in test stand running....icing was solved by a radiator type intake heater before the carb....a mechanical thermovalve controlled the heating based on the manifold fuel air temps.

 

short manifold paths are needed if your not heating the manifold