what is the difference between dual plane and single plane intakes?

what is the difference between single plane and dual plane intake manifolds? I was wondering and i just cant find no body that knows.  
SPRAY IT TILL UR OUT!!

dual planes have a dividing wall inside the manifold creating a smaller plenum area(the space inside the manifold that each individual runner pulls air from).  single planes as their name implies only have one large plenum area. larger plenums increase the available air and potential horsepower through increased rpms. this is assumming the heads flow well enough to need this.  for lower rpm use a smaller plenum(dual plane)  offers better throttle response as velocity is increased through the smaller area. single planes are not generally considered for street use but for race use as  part throttle operation is less critical. also engines that need a single plane are usually large flow heads with high rpm cams. these usually do not provide adequet vacume for power brakes etc. single planes can be used effectivly on the street but generally only on engines that were designed with that in mind.  

+1
mitch,,,
I copied and pasted a portion of your post, I think you meant to say, that, "single" planes are not generally considered for street use,,,,,,,,,,,,,,,,,,,,,,,.

this is your post below.
dual planes are not generally considered for street use but for race use as  part,,,
 
When The Flag Drops,,,



The Bull Chit Stops,,,


P. Engineer, Engine Builder

+2 yep yep good explanation  

Pretty good explanation. I would add that on a dual plane intake the drivers side of the plenum feeds the passenger side cylinder bank and the passenger side plenum feeds the drivers side. It has to do something with increasing runner length for greater torque if I am not mistaken.  

+1
Tuned runner length pulsed for velocity and torque
 
When The Flag Drops,,,



The Bull Chit Stops,,,


P. Engineer, Engine Builder

Edited post. forgot to think about runner length. anything posted under my name in this forum is open to be copied and used elsewhere.  

right on mitch, nice post
 
When The Flag Drops,,,



The Bull Chit Stops,,,


P. Engineer, Engine Builder

+1  
luck is when skill and opportunity meet

+2  
Professional hi-performance engine builder
Horsepower sells Engines and torque wins races.

Single Plane on the left (no divider in the Plenum), Dual Plane on the right (divider in the Plenum)

http://c2.ac-images.myspacecdn.com/images01/58/l_933c44baecbd74043401b42ecce7db61.jpg[/img]]  
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The Silver Buick- '77 Skylark coupe w/ a Fuel Injected Buick 455&TKO-600, '72 Centurion Conv't - 455w/TH400, '67 T-bird 4Dr (suicide) w/428&C6. '69 Firebird replaced!

http://www.bangshift.com/forum/index.php?topic=6189.0

mistermisfit:
Pretty good explanation. I would add that on a dual plane intake the drivers side of the plenum feeds the passenger side cylinder bank and the passenger side plenum feeds the drivers side. It has to do something with increasing runner length for greater torque if I am not mistaken.

The dual plane also keeps the air from getting lazy and the fuel settling out in the ports as the piston pulls air/fuel from a smaller volume, so air speed stays higher in the port (wet flow) and quicker vacuum signal to the carb for rpm changes.  I run a dry flow in my larger single plane intake (fuel is introduced at the port) so I don't get the lazy air bog at lower rpms that single planes can create with a carb (or TBI).  
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The Silver Buick- '77 Skylark coupe w/ a Fuel Injected Buick 455&TKO-600, '72 Centurion Conv't - 455w/TH400, '67 T-bird 4Dr (suicide) w/428&C6. '69 Firebird replaced!

http://www.bangshift.com/forum/index.php?topic=6189.0

I'm building a 350 chevy engine to put in a 85 chevy truck for truck pulls. what kind of intake should I use, dual or single plane.low speed high RPM (around 7000)  

single, because of normal operating range...7000rpm  

A single plenum is used for an engine like yours where the engine really has No sweet spot.Plus Higher RPM....    

Bob