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Discussion Starter · #1 ·
I guess this is as good as any place to open this. We have talked about a V6 serious build and balancing up, down and sideways. I have yet to see the intake port of a 3.9 cyl head in real life. It looks like the push rod bores are very in your face. In the past we have reamed the push rod bores to a true size machine a thin wall tube press it into the push rod bore then port to the tube and quit. That was on different 4 clys but it worked. Have others ported these or just accepted that they are designed for velocity? Steve
 

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Discussion Starter · #3 ·
Thanks I did find a link to the templates on another Dodge forum. Funny there was a thread like this on that board but was locked after 5 replies. There is plenty about doing V8 heads but it would be nice to hear from someone who has done V 6 heads and their results. After a month on this forum I'm enjoying being here and realize there are a few here who enjoy sharing. I came here for answers and help sorting out our truck. I realize this is a V8 / turbo / supercharger crowd. If I rebuild a 3.9 V6 I'll think outside the box but try and stay between the lines. Steve
 

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Discussion Starter · #4 ·
I now have a set of V6 heads and can better see the porting issues. I'll see what the templates look like and go from there. I also see there are no bores to sleeve so it's all about using what they give you. Steve
 

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I've read many of your posts & you are into some pretty intense stuff, Steve; as far as I go, I understand the basics of an internal combustion engine & try to know & learn enough to keep mine running well. Even so, I am interested in learning & knowing stuff that I will probably never use. With that typed, what do you get (performance wise) by narrowing the bores of the push rod ports?
Thanks/Matt
 

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Discussion Starter · #6 ·
I was thinking about cyl head porting issues I have faced in the past. Due to the way the heads are cast there is a hump in the intake ports. This hump is due to the push rod passing close to the port in fact partly in the port. If the push rod passed though a bore it would be simple to press a thin wall tube in that bore then grind away the casting in the port. Heads are not made that way so it does not apply. I'm learning everyday and that's what makes this so much fun. Steve
 
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