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Discussion Starter #1
I'm well along in my prep to assemble my cleveland. I'm using 2V heads, which I've already had bronze guides installed in and a 3 angle valve job, though I decided to acquire higher quality single groove valves from racer walsh, so I'll have to get them cleaned up to ensure they're 45 degrees on their sealing surface. After that, I'll lap them to match the middle angle of the seats individually and then clean the heads thoroughly.

The end of the valve guide bosses are concave from the factory....since the exhaust gasses flow up the stem of the valve somewhat, I made the end of the ehaust valve guide bosses slightly rounded (not so much as to thin them excessively).

The remainder of my work involved removing the parting line just above the seats. Nothing hardcore.

My question is (bearing in mind I'd like to hear from anyone who has ported any ford heads);

The little bump in the exhaust ports, which I believe is where the thermactor machining is done (if so equipped) is something I'd like to grind flush with the port walls. Has anyone here done this and had any bad effects?
 

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This probably doesn't help you, but I've done this to every Windsor I've ever built with Ford heads and have had no conequences, (exept better flow).

The exhaust side is where Clevelands need the most help. The Pro Stock racers used to mill the whole exhaust side off the head back to the valve cover rail and down to the head bolt level and install a port plate to enlarge and straighten the exhaust ports. I'd say that if you can cut the head back that far without carving into the water jacket, then you can certainly hog out the thermactor bump and the rest of the port past the valve cover rail. I'd throw an exhaust gasket on the flange and scribe around the inside of the port cutouts. Then gasket match to that and smooth everything back past where the bumps are and call it good.
 

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FYI, mpgheads.com sells plates Whisperer is referring to but you don't need to cut the head to use those varieties.
 

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The "thermoactor" bumps can be removed these are just a hot spot to help burn excessive exhaust gases on the way out of the
exhaust bowl.....

it is however......a good idea to smooth the inner radius on the bowl side of the port riser so that the kink on the Cleveland head isn't so bad.

ALso......get the valve guide stud and shape it as close to the shape of a tornado as you can.......where the valve comes out being the smallest and largest at the base of the bowl.

good luck
 

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Discussion Starter #5
I plan to stick with the idea that an exhaust port exit thats slightly smaller than the header opening is somewhat anti-reversion...I'm going to get rid of the downward curve of the exhaust by grinding the top.

I'm keeping the majority of the valve guide bosses since this is a daily driver.

Those plates that replace the outer third of the exhaust port are for 4V heads.

I doubt there will be a prob grinding these bumps.....but it'll suck BAD if I do end up busting (or burning) thru!!!
 

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Those aren't what I meant. I guess I wasn't very clear.

The Pro Stockers would mill the whole exhaust side of the head off level with the vertical plane of the valve cover rail, and down to the head bolt seats. Then a special plate about 1-1/4" wide and 2" high would go on. This would bolt down through the outside head bolt holes with special long studs and also bolt through to the inside of the valve cover rail horizontaly. The new port would mate with the old one just about the place that it starts to bend down and the new port would exit 1/2" to 3/4" higher then the original location. The increase in flow was great by eliminating the "hook" in the stock port.
 

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That's OK Hal....some of us knew what you meant, fellow OF...hehehe

I designed a similar plate for the 385 series heads...still have the prototypes sitting over in mom's shed. The things we would do...*G*

I think if our poster spends a bit of time in the bowl area cleaning and smoothing and removes the thermactor bump, he'll do just fine. I would usually leave the guide boss but would shape it as an airfoil, to lessen the turbulence around it as the exhaust gases flowed by...don't know if it helped but it sure looked pretty *G*

Sure is easy now when one melts a little plastic and gets alloy performance heads in a cardboard box...my, how times have changed
 
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