Started Porting the Heads on the Chevelle - Motorgen - Automotive Events, Meets, Cruises and Forums

94cobra69ss396 · 03-26-2009, 01:34 AM

I decided I needed to start working on the Chevelle since it's been sitting for such a long time. I pulled one of the heads and started cleaning up the ports and combustion chambers. I started tearing it apart at about 8 tonight and my wife came out and got me a midnight so I only finished a combustion chamber and exhaust port on one cylinder. I need to get more supplies tomorrow so I can work on it again tomorrow night. I'll also take some pictures of and post them up.

Glenn, do you have access to a flow bench? If so, would you be willing to flow my heads for me? I'd like to finish porting one head and then compare it to the other head before I port it.

BRUTAL64 · 03-26-2009, 11:05 AM

Quote:

Originally Posted by 94cobra69ss396

I decided I needed to start working on the Chevelle since it's been sitting for such a long time. I pulled one of the heads and started cleaning up the ports and combustion chambers. I started tearing it apart at about 8 tonight and my wife came out and got me a midnight so I only finished a combustion chamber and exhaust port on one cylinder. I need to get more supplies tomorrow so I can work on it again tomorrow night. I'll also take some pictures of and post them up.

Glenn, do you have access to a flow bench? If so, would you be willing to flow my heads for me? I'd like to finish porting one head and then compare it to the other head before I port it.

Unfortunately, the Flow bench I had access to is gone.

What I found is: if you use a flow bench, all you will do is drive yourself crazy. You'll be there for days. I once spent 3 days on one port.

big2bird · 03-26-2009, 11:10 AM

Port, polish, CC them and call it good.

94cobra69ss396 · 03-26-2009, 11:24 AM

Quote:

Originally Posted by BRUTAL64

Unfortunately, the Flow bench I had access to is gone.

What I found is: if you use a flow bench, all you will do is drive yourself crazy. You'll be there for days. I once spent 3 days on one port.

That's okay. The only changes that I'm making are porting them and then installing new valve springs so I guess I'll see if I did any good when I take it back to the track.

BRUTAL64 · 03-26-2009, 11:29 AM

Quote:

Originally Posted by big2bird

Port, polish, CC them and call it good.

Polish in not really needed. It's a waste of time on a street driven or race engine that is not torn down on a regular basis. A good smoothing of the exhaust ports is all that is really needed. You never want to polish the intake runner of a carb engine. When I do the Port Class for you guys I will explain all that.

big2bird · 03-26-2009, 12:01 PM

Quote:

Originally Posted by BRUTAL64

Polish in not really needed. It's a waste of time on a street driven..........

There ya go, talking about that primer paint job again.............

BRUTAL64 · 03-26-2009, 12:15 PM

Quote:

Originally Posted by big2bird

There ya go, talking about that primer paint job again.............

Primer is God's gift to the body challenged.

94cobra69ss396 · 03-26-2009, 12:25 PM

Quote:

Originally Posted by BRUTAL64

Polish in not really needed. It's a waste of time on a street driven or race engine that is not torn down on a regular basis. A good smoothing of the exhaust ports is all that is really needed. You never want to polish the intake runner of a carb engine. When I do the Port Class for you guys I will explain all that.

I don't polish anything. I do smooth out the combustion chamber though just to get rid of and sharp edges and I unshouding the intake and exhaust valves a little. I'm not doing too much on the intakes because they are already fairly large for this engine. I also know that the rough surface helps keep the fuel atomized and prevents puddling so even if I were to enlarge them I would keep them rough. However, I'm just smoothing the entry on them and blending the short turn radius because they left a little bit of an edge on the intakes. Most of my work is on the exhaust port. I'll take some pictures tonight and post them up.

BRUTAL64 · 03-26-2009, 01:16 PM

Quote:

Originally Posted by 94cobra69ss396

I don't polish anything. I do smooth out the combustion chamber though just to get rid of and sharp edges and I unshouding the intake and exhaust valves a little. I'm not doing too much on the intakes because they are already fairly large for this engine. I also know that the rough surface helps keep the fuel atomized and prevents puddling so even if I were to enlarge them I would keep them rough. However, I'm just smoothing the entry on them and blending the short turn radius because they left a little bit of an edge on the intakes. Most of my work is on the exhaust port. I'll take some pictures tonight and post them up.

Actually, you are doing it right from what you wrote. Can't wait to see some pictures.

94cobra69ss396 · 03-27-2009, 12:11 AM

Here are some pictures I took tonight before I started working. Since I already did one I took pictures of it and then of one that wasn't done yet. Sorry for the bad pitures but I didn't have very good lighting. As you can see I didn't do much to the intake port besides blend the end of the runner and smooth the short side radius which you can't see all that well. On the combustion chamber I just smoothed it and then unshrouded the sides by both valves. I didn't change the shape at all. The exhaust port is where I spent most of my time. I didn't touch the floor just the roof and walls and I smoothed the short side radius on it too. I also finished the second one tonight so two more to go and then I can pull the other head and start on it.