4 barrel 2.8 manifold

[Filister]

https://sfbay.craigslist.org/nby/pts/d/petaluma-ford-mustang/7442695923.html

Came across this add for a 4 barrel 2.8 manifold, if anyone is interested.

 

[spmdr]

WOW! Just because the CL add will go away, $500 !! $800 to replace!!

'gona keep an eye out for them!

 

[MikeH]

This modification of the 2 barrel intake appears to create a single plane manifold. I’ve read how a single plane can affect low rpm performance in a V8, but I don’t know if the same would be true for a V6. I believe the Offy intake is dual plane.

 

[spmdr]

1000 words (and almost as much $):

 

[260Alpine]

Offy Dual Port is more like two single planes stacked with smaller ports for low rpm and larger for high rpm. You probably lose about 10hp on low end but gain about the same on the top end with the Morana modded intake. That intake has the same ports as the stock Ranger which is a divided single plane with a 4 barrel top. Cheaper than a new Offy but still high priced for what it is.

 

[Barry]

The important difference between V8 single-plane and dual-plane manifolds is the length of the intake runners. The intake runners are typically "shorter" for a single-plane and "longer" for a dual-plane manifold. Shorter tends to favor high-end power and longer tends to favor low-end torque.

Note that the Morana 4-barrel manifold is actually two completely separate (side-to-side) three-cylinder single-plane manifolds with widely differing (about 1" to about 8") intake runner lengths. I suspect that cylinder-to-cylinder AFR's might be a problem with cylinders 2 and 4 tending to run a lot richer than cylinders 1,3,5 and 6.