Really dumb AV7 porting question

nick s /

So, this is my first time porting a cylinder, first time grinding through aluminum, first time making serious engine mods...

Anyhow, badmouth me if you have to, but at least impart some info if you're gonna do so...

I have two cylinders right now, an old one with trashed exhaust threads that's my practice piece, and my new one that I don't want to mess up. So, when I started widening the intake port, I first matched it to the 15mm malossi intake, and then made a smooth transition from that shape on the exterior of the cylinder to the widened dimensions on the interior cylinder wall.

When I did this, I encountered a different metal, where the new port profile intersected part of the area where the bolts go through the cylinder. Is this normal? Do I not worry about it, or do I need to avoid that area, and instead make the profile of the port kind of "hourglass" shaped? If I do that, though, wont it will create a pinch point and negate the benefit of widening the passage?

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