I gave up trying to make the runners transition to oval shapes
 on the bottom. I will just port out my cast iron end housings
 to round ports with a die grinder. I'll just squeeze the pipes
 on the center housing ports to ovals.

 These runners are made with one, one inch inside radius bend and one,
 two inch inside radius bend. About 3/16 wall in both cases.
 3/16 wall is about what you would get with a casting anyway.
 Apparently the reason they can do a one inch inside radius is
 because of the the thick wall pipe.

Paul,
Is there really sufficient material to port out the cast iron end housings to
round? Even if so, is it necessary, why not just make the round to oval
transition in the 1/2" aluminum plate for the manifold?

Bill Schertz
KIS Cruiser #4045

I think so on the early four ports. It won't take much. Maybe not on 
the third gen engines as they have bigger ports. I don't have any third
gen engines so I am just guessing.

A casting is the ultimate way to go but I don't think enough
people are interested to pay the cost of the pattern yet.

I busted my buns on that drawing getting it to clear the 
turbo. I won't know for sure until its done but plan B is space 
the stock turbo out a 1/2 inch. Things are that tight.

Paul Lamar
 
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