Originally Posted by LegacyRS

The problem with the runners is that the airflow is smooth and not very turbulent, leading to poor charge stratification...... The long manifold runners on the subaru's would encourage smooth airflow to my minds way of thinking.

Another point to note is that the further away from the port you are the earlier you have to fire the injector in relation to the actual valve opening, in acount of the volume of the air column inside the runner.

Also worth noting how hard it is to get the injector to spray down the runner rather than across it to wet the opposite wall of the runner. It's pretty hard to get a good 'shot angle' with weld on injector bosses and very difficult to get all 4 uniform on the same angle.

Why not go for larger injectors in the stock location?
Wouldn't that save the expense of someone butchering the manifold (and possibly getting it wrong)?