I've been porting a set of L98 iron heads the past couple of days and from what I have read, you're not supposed to polish the intake bowls and passages. Now this is to create some turbulence to keep the air/fuel mixture mixed up, but does that hold since on TPI since the injectors shoot the fuel directly in the head and it only has six inches or so to travel before the combustion chamber?

 

i remember something a while back that the fuel forms a fine sheet and it cant be reatomized or soemthing along those lines. This is probably caused by the fact that, like you said, their is a lack of apreaciable turbulence near the walls and the fact that the velocity approaches zero at the wall of the runner allows teh fuel to settle out. I dont know if its applicable to a batch fire system like yours wher ethe fuel just sits in the runners but hey, im no expert.

 

While the finer points of Laminar flow are going to have to wait Until later in my educational Career, I think the "experts" on this site will agree that polishing your intake tract to a finer than "sanded" finish will have absolutely no positive effect on performance, and may even cause some fuel puddling issues (unlikely with port injection, however )

The best analogy ive ever heard, is think of a River.

The water near the sides dosent flow very fast in relation to the middle, does it ?

So concentrate your time someplace else.