which is better? i thought dual... but maybe im wrong...

 

Each has its strong points and weak points and the correct one to use depends on the application and the goals. Dual plane 'generally' is used for lower RPM use and open plenum 'generally' is considered needed for higher RPM running.

 

this is just going to be a street car...

 

Personally I have found both work well on my street car, but I made power at a lower RPM with the dual plane. It really depends on the rest of the combination but again 'generally' people seem happier with dual planes in mildly performance enhanced street cars. I am also obviously speaking very non-commitial intentionally to avoid turning this mild mannered thread into an all out debate/war from 'absolutists' who are fully entrenched in one camp or the other

It really does depend on so many factors both mechanical and mental what is the best choice. Even on the same motor mildly build up motor both will perform well. One might make slightly more HP while the other 'feels' stronger for a because of a difference in peak or how level a torque curve is.....

 

you need a dual sean it will have better manners esp since its your dd isnt it?

 

its going to be, yes

 

I wouldn't put a single plane on a DD unless it were a stroker. Like dodgestang said, there are a lot of factors that effect how the intake will perform. A stroker will move more air more rapidly, making any intake used operate in a lower than advertised range for the engine it's on. In other words, something like a Vic Jr that's designed for 302's in the 3,500-8,000rpm range, on a 347 would be more like 2,750ish-7,200ish. It also depends on where all the other parts can operate at, what kind of mileage you want, throttle response, what your cruise rpm is, how much bottom end you're willing to lose etc.

I prefer dual planes for most street builds. Single planes can work if you know how to make them.

 

+1 on the dual. I am building a stout 383 stroker, and I am still going with an Air Gap. They just do better if you arenot going to run north of 6500 all the time. I really thoughtabout using a single plan but could not see how the number would work for me even running a stroker with power adders.

 

+1 for the dual plane. Like urban_cowboy, I am using the Edelbrock Performer RPM Air Gap manifold. Great for a DD.

 

i'll tell ya what, just cutting the divider down on my performer RPM robbed me of bottom end grunt. it was a difference that was very easy to benchmark against as nothing else changed.

did it help up top? probably. would i cut it down all over again if the intake was new? probaby not as i could use more low end grunt with the cam i have