I wonder about using a high temp epoxy putty, such as Bruce uses in his video for smoothing out the intake ports. It may be a non-issue since I dont anticipate using the stock intake apparatus

Dave

DaveLeonard wrote:

Oh thooose holes.  They are the ERG passages.  Used for smog reduction.  The should be plugged - by the intake manifold.  When I rebuilt my engine the consensus was to pack them with potters clay, bake, and repeat.(JB would never hold up to the exhaust temps).  I did that but don't recommend it as I still occasionally get pieces of clay coming out the exhaust.  Luckily they haven't hurt the turbo yet.

 

Since I am using the stock intake manifold I had to weld the passages there.  Aftermarket manifolds should cover them without having to be modified.

 

Dave Leonard

 

So far, my questions are as follows:

1)    On the intake side, there are several holes that appear to be 
water jacket holes for the intake manifold. I want to say I was told 
these are for warming the intake manifold with hot water for emissions 
purposes. I have yet to see an aviation intake that uses these holes. 
Plug with JB weld or epoxy putty?

    

I'm not sure which holes you are taking about.  The water feed to the manifold is a large hole in the outside of the rotor housing.  I am actually using it in mine to feed water to the tubo but it is not otherwise needed.  Those holes are far too large to plug with JB.  The intake manifold fits over them and will seal them off, or you can get a plug designed to fit in one.

Ok, on the 4 port block, there are square holes underneath the intake ports located in the end and middle "side" housings. Now that I think about it, none of these ports had any rust or rust dust on them so perhaps they are not water after all, but as someone else had said, tied to the exhaust. I probably need to trace the ports to truly know what is going on there. On the aluminum rotor housings themselves, there are two round ports that did have clear evidence of water jacket circulation, located above the exhaust ports where a "peripheral intake port" would be located (if the engine was peripherally ported).