308 heads

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flathead5173

flathead5173

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I have a set of 308 heads that I'm going to install 2.02 intakes in and do a little bowl work. Do you have to worry about hitting water when working on the bowls of these heads. The exhaust valve is nailhead type and the 1.88 is a tulip type should I stay with the the tulip type in the 2.02 or switch to a nailhead.
 
Imagine what the ports look like from the side as if you had the head on a flat surface and are looking at it as if it were a cross section diagram.

On the intake side, there is a water jacket right underneath the short turn and in front of the valve guide on the intake manifold side. There is also water on the other side of the seat on the intake manifold side but not as close to the surface as the short turn area.

On the exhaust side, there is water surrounding the valve guide but it gets pretty close to the surface between the guide and intake manifold and between/above the valve seat and guide boss. There's also water between the valve seat and intake manifold but it's not as near to the surface as in the other instances.
 
If you are not doing more than bowl work I would stay with the tulip valve. Also, if you have a 5 angle valve job done, all you need to do is blend the throat cut a little and that's it. Don't hog things out. The exh port is very good as it is, so again, dont make it bigger "just because". less is more.
 
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