My 18cc ported Honda head

[David wulf]

Started this yesterday and I'am just about finished , still want to address the valve guide in the intake port a little . One think I want to say about my porting is you'll see that the exhaust is polished , not like a mirror but enough to work fine . And when I do these ports I look at the exhaust is going out and to work the bowl in that direction. As with the intake the air is coming in so it should flow that way . Also with the intake it was pretty smooth from the sanding rolls used for shaping, but is finished up with a stone to roughen and to give it a swirl pattern . You do not want to polish the intake port , the fuel and air will not mix well that way .so that said here's some pics . Oh and one more thing the head has been sanded on my marble slab , took me two hours . It has had 53 thousand taken off . So with the piston 9 thou ITH and a 10 thou head gasket and the Honda flat top piston . This will give me a compression ratio of about 13.6 to 1 . Yes race gas for sure .

 

[David wulf]

Forgot one thing the port floor or I guess short side radius. If you stick your finger in these ports you will feel a sharp edge . The trick to that is cut it out and shape it into the valve seat , when you see sparks you in the seat . This is the most important part of the hole process along with the bowl area and around the guide . As far as the port goes I did not enlarge it just got it smooth . We're looking for velocity here and hogging out the port doesn't give you that .

 

[ole4]

Looks very good, be careful with the SSR if you lower it trying to put too much of a radius you can kill low lift flow. Just smooth it. The best way if fill the floor and with it raised then you can use a radius tool and get a bigger radius. I usually raise the roof to round the top where the bowl cutter machines it flat so I still have the same cross section area. What are you doing with the seats as far as angles?

 

[David wulf]

As far as the seats go nothing but as it is stock . I have no way to cut them .

 

[delray]

Hey david,looks good.
I got a question about grinding part of the guide down. Is there any big gane doing that to a mild lift came setup or more just for high end performance.

 

[David wulf]

Brian I think anytime you port it will help the motor . Even on a stock motor it will help move air in an out better , win win . Now if one was really making the ports bigger it would not help a stock or moderatly built motor . All I have done is just smooth everything out , taken all the rough edges out and put a radius on the port floor .