porting kit ?

There are two basic types of die-grinders: air powered and electric. Both take 1/4" shank burrs and I recommend carbide even for easy-cutting aluminum. The air grinders are cheaper and run cooler but you will need a pretty big compressor to run one. If you go with air, before each use, squirt some oil on the air inlet hole- this alone will extend the life of these little grinders by maybe 6X. There are also front exhaust and rear exhaust; front exhaust may disturb the grinding dust in ports, making it hard to see what you're doing.

It's surprising how hot the protruding snout of an electric die-grinder gets after 5 minutes of use. When I had only an electric one (Sears Craftsman) and was working on cast iron, I wore welding gloves....

These days I lean towards only profiling the portions of the valve pockets and combustions chambers into and out of the valve seats, and sizing the valve throats. Of course sharp edges, ridges, etc should be removed everywhere. For a Pantera the flat roof in the exhaust valve pockets and the bump in the exhaust port roof can be eliminated. Street engine throats should be 85% of the valve head OD max, or enough to get the sonic choke above red line as a minimum. You need room for a 0.060 wide intake seat, or a 0.080 wide exhaust seat, plus the 30 and 60 degree angles on either side of the seat. Roughly 0.3 inches less than the OD of the valve head, this applies to both intake and exhaust. Its very easy to open up the throat of the 2.19" intake pockets too far, and ruin the venturi. They are 1.75 off the shelf, and 1.90 is about the max you can take them. Caution must be used to not go too big.

I've always relied on others to perform the valve seat jobs, I've never owned valve seat grinding or cutting equip. But I always perform the valve guide work and pocket and combustion chamber blending work before I hand the head castings over to the seat grinder. Once the seats are ground that establishes the valve heights. I perform the spring seat work and rocker arm pedestal work (if any) afterwards.

Its common these days to completely remove the cast-in guides and press-in the exposed style of guides. The upper part of the guide, in the middle of the spring seat, can be knocked down with a fly cutter. The guide within the valve pocket will require a burr to knock it down. Sealed Power (Speed Pro) part no. VG-7501R is a universal guide that is almost exactly what is needed for the 351C, except its too long (assuming the valve stems are 0.3415 OD). It should be shortened to 1.625" insertion length (length below the flange). Once its pressed-in it should be sized with a 0.3430 reamer.

Match the head's port inlets to a gasket, just clean up the intake manifold runners if needed. They don't need to be matched, the head's port inlets should be bigger than the manifold runners, so there's no ridges in the air stream.

Monty, you mentioned doing the "essentials" but that left more questions in my mind than anything else. I mention all the above to clarify what "could be" essentials, and thus what tools, bits, sanding rolls, etc you'll need to get it done. Anything more than that is not an essential. Cleveland heads require less work than any other muscle car era head. Nothing major needs to be moved, nothing needs serious resizing, etc. All of the work excepting the seats I can do on my own, with a drill motor and some fly-cutters, a die grinder and sanding rolls, and a press and a reamer for the guides.

You asked about electric die grinders, Milwaukee, Bosch, or Makita, take your pick. The draw back of the electric die grinders is that they are heavier, and larger (more cumbersome) than their pneumatic counterparts. There are inexpensive sanding roll kits on eBay and at Summit Racing, check them out as a means to get started. The spring manufacturers, valve manufacturers, rocker arm manufacturers will have the cutting tools for their stuff. I always prefer Manley. McMaster Carr supplies a lot of the other stuff ... but there are other machine tool suppliers other than McMaster. McMaster is expensive but they ship FAST!

Getting ready to do a set of D3ZE heads myself.

Edited to add picture: The picture displays how the valve guide casting has been knocked-down and an exposed valve guide has been installed. It also reveals an excellent job of blending the pocket into the throat, the throat into the seats, and the seats into the combustion chamber. If you want to spend time on the head ... this is where to spend it, knocking down sharp edges, steps, and ridges and blending the various surfaces and contours. All while removing as little material as possible. The "pretty" work in the pocket and port are not as productive, but it sure is pretty. I have one suggestion, the valve could have been unshrouded better from about 11:00 to 1:00 in this picture (I make that comment a lot).

The iron 4v heads are nothing for an amateur to fool around with.

Probably the only thing that you should do is put a nice three angle valve job on the seats and blend the 60 cut into the pocket.

Other then that, leave them alone.

They originally had a "venturi" ring cast into the pocket just under the valve to increase velocity into the cylinder.

When you go racing, usually you cut that out. In a street car, you leave the ring alone.


If your guides are shot, go with the full bronze press in guides and just clean up the cast iron pedestal.

Under NO CIRCUMSTANCES do you polish the intake ports. Leave them rough. That helps keep the atomized mixture in suspension.

Stock heads have shown that they will flow right around 300 cfm at .600 lift with just a nice 3 angle valve job.

Race 289 and 427 heads are around 250 to 260 by comparison.

If anything, the heads are border line flowing too much for only 351 ci UNLESS you intend to turn the engine to 8,500 rpm.

It is much safer to take the heads to a very experienced FORD engine shop like Joe Lapine at Danbury Competition.

Let him worry about the details and do what he says to do to them.


I've burned out two of the Sears Craftsman, and the Makita. Currently I'm working on killing a variable speed Roto-Zip. I like it but I hear it "going".

On iron you can use the blue stones. On aluminum you need a pure carbide cutter. The teeth are wider apart to aid in keeping the aluminum from clumping and clogging the cutter. It still does but at a slower rate that you would use on an iron head.

There is also a "cutter lube" that you use with aluminum. You just dip the cutter in the dip and it aids in keeping the aluminum cutter clogs off the cutter.

There are carbide teethed pocket cutters that you can buy in three different od's. They are about $150 each but the advantage is that you just make one plunge cut with it to clean up and shape the pocket.

They already have the shape of the pocket machined in them, so just a slow plunge cut with a drill press or mill will save you hours of time.

It works great on Windsor heads and Chevy's. In fact some of the shops call them 'Chevy pocket cutters'.

I have not used them on a Cleveland and doubt that they would productive, just destructive.



Ported heads are always a risk. For one thing the walls of the ports are only so thick. The other thing is that there can be casting "drop outs" left from the casting process.

They are a little smaller then the size of a pea. If you run into one it will fall out of the port wall and leave a hole through to the water jacket.

IF you have to go into the port to weld up a flaw, as far as I am concerned, the head is junk. Throw it away.

Like I said, best to leave it to an expert. It's true that if you want to be a 'porter' you need to start some where. I can count three sets of heads that I started on that aren't even good paper weights now.

I think cast iron is about $100 a ton in junk? Aluminum is better. About $.23 a pound last time I looked? Maybe better now?

quote:

knocking down sharp edges, steps, and ridges and blending the various surfaces and contours. All while removing as little material as possible.

This is where I will be spending my time. Thanks for the advice. "Less is more" I get that.
What about the hump on the roof of the exhaust port? In a Mustang with headers does this help direct flow downward or should it be eliminated regardless of application?
Should the material around the intake valve guide be teardrop shaped to help direct flow away from the cylinder wall, eliminated completely or left alone. Seems to me leaving some cast iron around the valve guide helps dissipate heat from the intake vale. I'll not do much here as the Ford Engineers had things figured out.

Have fun but when the builders tell you to DO NOTHING to the ports that is very explicit.

If you want to learn to port heads, you can get a set of "junk" 289/302 heads and work on them.

There are loads of bumps and restrictions for you to work on.

The valve pockets need to be hogged out. The guides need to be REMOVED. The valves need to be enlarged.

You will absolutely love it.

Just for jollies, weigh them before you start and after you are done.

They start at around 55 pounds each and wind up somewhere around 50 per head.

Bizzzzzz!

quote:

Originally posted by LTP:

What about the hump on the roof of the exhaust port? In a Mustang with headers does this help direct flow downward or should it be eliminated regardless of application?

The flat roof in the exhaust valve pocket and the bump in the exhaust port roof were placed there to encourage exhaust gases to flow downward into the exhaust manifolds. They should be beneficial for any exhaust system that turns abruptly downward to hug the side of the engine.

quote:

Originally posted by LTP:

Should the material around the intake valve guide be teardrop shaped to help direct flow away from the cylinder wall,

No. It would be better to remove the valve guide casting all together.

quote:

Originally posted by LTP:

Should the material around the intake valve guide be ... eliminated completely or left alone.

The trend today is to eliminate it completely ... as in the picture I posted.

quote:

Originally posted by LTP:

Seems to me leaving some cast iron around the valve guide helps dissipate heat from the intake vale.

The intake valve runs "relatively" cool, it is cooled by the incoming fuel and air charge.

quote:

Originally posted by George P:

quote:

Originally posted by LTP:

What about the hump on the roof of the exhaust port? In a Mustang with headers does this help direct flow downward or should it be eliminated regardless of application?

The flat roof in the exhaust valve pocket and the bump in the exhaust port roof were placed there to encourage exhaust gases to flow downward into the exhaust manifolds. They should be beneficial for any exhaust system that turns abruptly downward to hug the side of the engine.

Just to add interest to that thought, I was told, rightly or wrongly, that the proper way to flow an exhaust port is with a stubby tube on it. It should be about 6" long and have a 3" radius. The tube is pointed directly down.

I seem to remember a Hot Rod magazine article/test where they attempted to verify the exhaust flow improvement with various configurations.

I don't know if the test was rigged but the best flow was with I just stated. They might have been BB Chevy heads? It doesn't seem logical that ALL heads would react the same way.

Just food for thought.

quote:

Getting ready to do a set of D3ZE heads myself.

It would be really helpful if you posted some before and after shots of any work done. Especially in the pocket. I think was getting overly ambitious about working on my DIAE heads but I still want to blend in the sharp edges that I can feel with my finger. Any of the machine work (valves, seats, guides....) work will go to a professional shop.
Does anyone have a recommendation for a shop in Vancouver? I've got family is S.Oregon so even a shop that far away is an option as long as its not too far off the I-5. I can always box the heads and run them to a depot across the border in less than an hour.
Monty