Hi Hoggy - welcome to the site. It depends a lot on the car make. The holes (ports) may be larger in the 1.4 which is good for airflow but the spacing between the ports can also vary so if these are in the same location you should be able to use it without any problems.
The ports inside the engine also need to match for maximum benefits and it would be possible to wreck the airflow by going from large aperture to a small aperture. If we are talking induction manifold you will also have the benefit of bigger injectors.
Hi Hoggy - welcome to the site. It depends a lot on the car make. The holes (ports) may be larger in the 1.4 which is good for airflow but the spacing between the ports can also vary so if these are in the same location you should be able to use it without any problems.
The ports inside the engine also need to match for maximum benefits and it would be possible to wreck the airflow by going from large aperture to a small aperture. If we are talking induction manifold you will also have the benefit of bigger injectors.
Sorry - didn't mean to confuse. I just meant that while fitting a new INTAKE manifold you would may as well use the injectors fitted to it which are typically higher rated therefore deliver more fuel (manifold plus injection rail etc...) .
Just to clarify.. There are two manifolds on an engine. Since you didn't specify exhaust or inlet manifold, Wayne assumed that you meant exhaust, as this is the more common of the two to modify.. He also gave details on inlet manifold, just incase thats what you meant..