see all the fun that you are having with making your own manifold. noob, take the factory header off..... put it on some template material (cardboard, or doorskin). clamp it down to a table so you have the factory header flange ontop of the template material. spray paint the outline and the stud locations. The part that is not sprayed is the flange!!!!. YAY now take a razor blade and cut off all the painted areas. be sure to use a center punch to get the center for your head stud locations. yada yada then you have your template. take your template and put it on your choice of material for your head flange. use some high temp or vinal spray paint the image of your head flange on your flange material. Then put it in a mill, with accurate hands it should come out semi okay. Or if you have access to a cnc machine, well you would know what to do if you did.
it may seem simple and if you think its simple... lol your gonna have fun. I have a good 15 hours in design and redesign of my manifold and i would still make alterations, i was not crucial on airflow in my design either.
ive told too many people this, DO NOT rush any turbo install or engine swap. there is no reason to. it will just cost you more time in the long run.
*edit* - holy crap, why didnt i think of this before. you can save your self all this aggervation if you would go to South Florida Performance and buy a head flange from them for the ka. You can get your turbo flanges there also !!!!
