Hey guys, I am porting a VVT head for forced induction and I had a couple questions for the more experienced here. I am planning to polish the chambers and after I CC the chambers tomorrow I'll be at that point however as this will be used with forced induction I was thinking about softening the sharp edges as well.

- Do people generally reshape and blend #1 into the combustion chamber or is that largely left alone? If it's left alone, is it alright to soften the edges (where the #1 arrows point) to reduce hotspots?
- With #2, the chamber to valve seat recess from the seat pocket machining - should I soften the edge, leave it alone or blend that in so there is a uniform transition from the valve seat to chamber?

 

In general yes that needs blended into the seats, it will help low lift flow.

 

About what I was thinking based on what I have found across the internets. I was looking at the valve seat to chamber recess (#2) and thinking it might be used for low-lift turbulence but there's surprisingly limited information about features such as these, just a lot of 'look at my bling!' photos for the most part.

 

I smoothed mine out like you mentioned. The only reason( I can see) that is there is it is in the casting and the cutting tool for the seats leave it looking like that. In the MFG process its not worth cleaning up so a little massaging would MOST LIKELY help. I would be very surprised if the intent was, as you mentioned, inducing turbulence vs just ease of manufacturing.