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Discussion Starter #1
This guy is trying to sell me the 781 heads he has on an old block , but I’m not convinced that they are what they say they are..He told me that they have been ported but they look untouched to me let me know what you think
 

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True Hotrodder
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little hard to tell from the one photo but I do see a little bit of marking on that side wall but the bottom of one port looks untouched. The greater flow is at the sides and roof of a port. They may have ignored the floor as there isn't much gain to be had there.
 

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I agree, not really a good enough picture to tell much...but to me it looks unported due to the casting mold lines half way up the side wall in each port.
The port on the left, #2 intake, you can see the casting line on the 'hook" side of the port, which should be left alone even if doing a full port job as that side of the port is a dead area and making t bigger has negative consequences for flow.
HOWEVER
The port on the right, #4 intake, that casting line visible is on the long wall side of the port, and if it was fully ported nearly .100" of material should have been removed leaving absolutely zero trace of that cast line on the port wall.

Need better pictures of the ports, and he should be able to send you pictures of the valve bowls and combustion chambers too, and he should be able to tell you what size valves are in there.
Under a magnified view, the ports look completely stock to me.....at least as far as you can see in that pic. Doesn't look promising.

Stock 2.065" intake/1.72" exhaust valves means NO DEAL, regardless of what has been done to the ports....a proper full port job would also have included cutting for bigger 2.19/1.88" valves. If the bigger valves weren't added but port work was done, it would have to be completely re-done once the bigger valves were then cut in....and without the bigger valves any port work with stock valves helps very little.
 

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My impression is not at the top of the runner that is visible. As Ericanova points out the paste line where the upper and lower halves of the casting cores mate are visible, porting even mild porting removes these from sight.

Blowing up your picture it looks like the surface is simply raw rough casting, which in an unmolested port will have the same surface quality of any part of the head casting that wasn’t machined. Missing are the grinder serrations which leave lines in the metal in what is called normal to the flow direction which simply is 90 degrees to the flow. There some people that polish these out in which case the port walls would be slippery smooth.

Now what can’t be seen from the photo is what if anything was done in the valve pocket of the port. This is where most flow obstruction occurs and might be ported, you’ed have to get an inspection camera in there or pull the head and pop out a valve to see. Given that about 80% of potential flow improvement is in this area and if this was built to race under some association rules it is not uncommon to find heads that are only “pocket ported”. So before anybody gets labeled as a ‘story teller’ you need to see into the valve pockets.

Bogie
 

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the Port on the left looks like the surface changes at the short side radius.
stick the camera in the port and take another pic
 

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Looks l;ike a little bowl blending was done, but not all that much....hardly a full port job.
Valve doesn't look like a stock piece, but that's just going off looks.
Any idea of what valve diameters are in it?
 

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Discussion Starter #9
Looks l;ike a little bowl blending was done, but not all that much....hardly a full port job.
Valve doesn't look like a stock piece, but that's just going off looks.
Any idea of what valve diameters are in it?
I haveno idea. I bought the rotating assembly. The restwe got from a 1982 454 engine laying around
 

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Race it, Don't rice it!
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Doesn't look worked on to me. It's standard practice to blend the ports around the newly installed seats as there is often a ledge or shoulder or a bit of over hang between the seats and existing port. It's basically done to smooth the transition after a seat and guide work is done. Usually done with a carbide burr but sometimes done with a cutter in the seat and guide machine depending on the shop and the quality of details they send out.
It's pretty funny a shop might put on the work order (bowl blended) or something along those lines and then somehow the word "ported" get in there instead.
 

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Excuse my ignorance but what is blending
Blending is breaking sharp or sudden dimensional changes to join then as smoothly as possible given the limitations of material shape and dimension differences. Probable the most common is smoothing the underside of the seat into the port wall. But this applies to any abrupt discontinuity of shapes and dimensions.

Bogie
 
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