I decided to go with the original B18 head after talking with Phil. I can still use one of my B20F heads later if it doesn't turn out as well as expected. By the way this head was rebuilt some 40k miles ago & the valve guides protrude way down into the port. Looks like the same guides were used for both intake & exhaust & not cut off for the intake like it should have been. Is this normal on a rebuild or are there 2 different guides for intake & exhaust? I'll probably have the guides cut down & shaped to limit restriction despite the fact that the intakes don't usually need too much work. Maybe a little pocket porting too on the exhaust to clean it up. Nothing too radical though ;I haven't got that much experience porting & I understand that these are a little tougher to get right than some other engines. Thanks for all of your input I enjoy all of it!

Mike M.