I just got finished porting/polishing my heads. I got my "technique" from a combination of David Vizards book on head porting, reading posts and writeups on here, and tips from my dad.

For my first time doing this, I think it turned out pretty decent. All that's left is a 3 angle valve job and some new valve seals, and they're good to go.

Any comments, tips, or the like would be welcome. Especially before I get the valve job done

The first pic is the exhaust bowl area.

 

Intake bowl area

 

Exhaust port

 

Intake ports.

Also want to add that any constructive critisizm is also welcome. Like I said, it's my first try at something like this.

Also, for those of you who haven't done it yet: It's a filthy job. Definately one of the dirtier ones to do to a vehicle. Expect to have metal shavings in your hair, in your mouth, in your nose, and some will get in your eyes. I was wearing a face mask and safety glasses the whole time, and it still managed to get in those places. I'll be tasting iron for days

 

I think it looks pretty darn good. I am currently working on porting my old 416's.

 

Thanks ;D Good luck on your heads, from what I read the 416's are almost identical to these.

Also, the last pic is upside-down. The rough area at the top of the pic is the floor. The narrower smooth area on the bottom is the port roof.

As far as time goes, it took about 12 hours from start to finish. I already had them stripped and cleaned. Used carbide bits and finished with standard abrasive's polishing kit.

 

Looks pretty good for you first try. Make sure to gasket match the intake to the heads, and the exhaust ports to allow better flow in and out of the heads. Other then that you appear to be on your way to some cheap extra power...

 

Hey those look great. Are you getting them fitted with larger valves? When ported like that the 081 heads are awesome for a 305.

 

Thanks guys! For the intake port matching, all I've done is raise the port roof to the gasket line. I'll probably follow your advice and port match the exhaust to my new headers tomorrow.

I'm gonna just stick with the stock size valves for now, I only plan on using the 305 shortblock until I lunch it. I also didn't want to deal with the shrouding, and I don't feel experienced enough to do heavy porting on the combustion chamber to combat the shrouding.

What kind of flow gains do you think I'll see with this? I did it mostly as an efficiency mod and for practice, the power's just gonna be a bonus

 

You are going to have to have them flow benched for that. You can almost double the flow numbers on some GM castings.

 

definately need to scribe some 1405's on there and get rid of the intake runner volume gm seems to "add" but other than that they look good. would like to see the exhaust bowls too.

 

Dont gasket match on the exhaust, leave a slight wall for pressure waves bouncing back, you want to leave about .062 wall, most of the way around. But do match on the intake.

 

The exhaust bowl is in the first pic.

Unfortunately, I got to greedy today and port matched the exhaust port back to far. Burned a hole thru to the coolant passage at the beginning of the port...

Since I need new heads, I'm gonna get some aftermarket ones. Gotta do some research on what will work decent on a 305, and a 350 later down the road.

Oh well, live and learn I guess. I can guarantee that I won't make that mistake again Just sucks, because now I have to shell out some cash that I wasn't prepared to spend right now.