The integral head has the intake cast into the head, its all one piece. The intake runners are small and not well designed. The exhaust manifold comes off I think??? not 100% sure of that, but it to is a piece of smog crap. Its a very poor design for any kind of performance use. There is no headers or manifolds that work with this head. I threw mine away, never even looked at it!
The early heads with smog tubes are just the same as those with out. They simply drilled holes in the outer part of the exhaust port so the could inject fresh air in to the exhaust flow. The fresh air would help burn out some of the emissions. You can plug them very easy.
All of the other heads are so close in CC's except the 194, that they can be swapped with no problem. Intakes are all the same design as well as the exhaust manifolds. The later 292's might of had a different flange at the pipe outlet, but port design was the same.
The real difference in 230/250 and the 292 is the bore, stroke, block height, and camshaft. All the other parts will interchange. The cams will interchange as well if you use a electric fuel pump. Joe
