I'm bored and I have a minigrinder. Hmmm. . . .

Waiting out the Nor-Easter here on the Eastern Shore, VA. Can't work. So I started porting my head. This head is a 1g head off an n/t block.

I read the nice little write up here about mild porting your 1g head. Great stuff. I can see how there would be a gain. The valve bowls are hardly conducive to smooth flow. There's imperfections, lips, and other stuff going on right where the port turns into the valve opening. There are many casting imperfections.

Also, specifically for the short side radius of the exhaust ports, there's a nasty almost ripple series of rises. . . at least on this particular head. This took ALOT of "touch" to remove, because I didn't want to alter the shape of the port. There was no ripple in short side radius of the intake port, however.

I should have taken a shot of the exhaust ports before doing this work. But here's the finished product on that side at least.




I will start the intake side soon. Here's a few shots of the imperfections. Here's where the gains probably will be the most, because the lip is a direct step down in diameter, as the exhaust lip is a step up in diameter:



Here's an example of some weird shapes in the intake port. There was this kind of stuff in the exhaust port, too:



Here you can see that nasty ridge at the intake port bowl. I'll bet the airflow here at mid valve-lift is like ! Also this was at the exhaust port, but the exhaust gases are not as affected by this because this becomes a step out.:





Nevertheless, a smooth transition is still better. So they got ported there too. None of this was about reshaping the ports, just cleaning them up. I will still need to go into the exhaust manifold side of the ports and clean up the casting imperfections.