Mark A Shields

For those that don't know I just got some aluminum Pro Lightnings, unfortunately I can't port them, but I want to polish them.

What is involved for this, what materials/tools are needed? thanks

Rustydawg

I would be tempted to start by hand with a variety of emery cloth grits and go from there to be safe. You know how aluminum fills grinder bits and tends to grab & chatter? It can make a mess in a real hurry.

I assume you're just doing the exhausts?

ede

why couldn't you port them? you'd use the same motor to drive a cutter as you would emory. if you have a file made for steel use lot of oil on it to keep it from loading up, if it's made for aluminum use a lot of oil on it anyway.

Mark A Shields

ede, as you're well aware, I'm sure, lol, I'm not very good at workin on cars, so I don't trust myself porting the heads. My bro was sayin to use a dremel to polish them, I forget the kind of part he said I would need for it. This a bad idea? I was just going to watch him do it for the experience... he's worked iron heads before, but I don't think he's ever dealt with aluminum ones.

F-BIRD'88

Do Not polish the intake port.

87transam5.7tpi

you should only polish the exhaust ports. you want the intake to be somewhat rough so the air has turbulance to mix w/ the fuel better.

Mark A Shields

just wondering why not?

oh, and sorry I don't have pics yet, I'll have them Sunday when i get back to college, but the ports on them are so smooth, doesn't seem like they would need much porting at all, if I were to port just to smooth them out.

87transam5.7tpi

check out my post right above yours.

Mark A Shields

lol, thanks, guess I was replying while you were too.

87transam5.7tpi

ya thats is what I guessed, I wasn't trying ot be a jerk. I've just missed posts before so I thought I'd make sure. nothing personal

Josh

F-BIRD'88

You can clean up the port walls with course 40# 60# emery rolls
don't go any smoother than this.
A 5/16 to 3/8" rat tail file that is cut off and shortened to go into a 3/8 drill works good too. Leaves the right finish on the port.
Do not reshape the port other than blending any ridge left by machining in the bowl. You could carefully streamline and thin the valve guide boss to.
You want the intake port opening to match the manifold opening, not the gasket. But you use the gasket as a guide.
You can do the same on the exhaust port. you can polish the
&*^ out of the exhaust port if you want.

Use lots of WD 40 to stop the alumiun from clogging the file.

There is not reason to get any where near the valve seats.

kfoley

Porting is easy... just take it slow. I'm working on a set right now (although not aluminum). You might also take a look at Sitting Bull's thread about porting 305 heads (but I'm guessing you already have).

Sitting Bull

Did someone mention my name?

Hah, hah!

Don't sweat it Mark. I was kind of freaked, too, when I started. But you learn very quickly that porting, polishing and bowl-blending is a VERY deliberate process. You just have to keep in mind what you are doing and don't day dream. Then again, the thought of butchering an $800 set of heads has a remarkable way of sharpening your attention

You can do it

Kevin Johnson

A quick and inexpensive way to fairly evenly smooth minor imperfections in the port:

[Use a die grinder for this; Hobbyist Dremel doesn't really have the torque you'll need nor thick enough mandrel shafts]

Buy a length of 3/8" mild steel rod (tool steel if you can find it).

Cut to length: 5-6" is ok.

Cut a narrow slot in the middle of one end. Maybe 1 1/2" deep.

Go to Home Depot or Lowes and buy the cheapest belt sander belts you can. I usually use a medium grit.

Tear the belt in half crosswise.

Tear lengthwise strips down the belt that are about the same width as the slot you cut in the rod. Make the strips several inches long.

Find out with direction your die grinder rotates.

Insert one end of a strip into the slot (crimp it a little with pliers if the fit is too loose). Wind the strip with the abrasive side out around the rod. Do it so that when the die grinder runs it will try to 'tighten' the strip. This might sound complicated but after one or two tries you'll be an expert.

PUT ON YOUR PROTECTIVE EYEWEAR.

Place the wound up strip/rod into the port and start the die grinder. Away you go! Works great!

You can put a highly polished surace on by using fine sandpaper strips. Only problem is that paper-backed products don't last too long. Seems like Swiss cloth backed sandpaper would work better albeit more expensive.

Be VERY careful in the bowl area lest you sand the sealing area of the seat. I normally figure, though, that if I am doing porting work, a seat touch-up is automatic.

If you could run a shopvac or similar near the end of the port while you are doing this your visibility will improve.

HTH

Guest

There is fuel on the intake side, that you want to keep in suspension and get it into the cylinder. With polished ports, the fuel can and will stick to the ports, and not flow into the cylinder like its supposed to.

You can clean them up with a dremel just fine. If you plan on doing anything to the heads inside the ports, you have to take the valves out. I would highly recommend marking them or somehow keeping all parts in order, and reassemble in the original locations. Hard to say if all things are equal, there may have been variances that the manufacturer knew about and corrected.

I would concentrate on the bowl and seat area, and forget the rest. Blend the seat into the port and chamber, maybe grind some on the valve guide boss (stay away from the guide itself) and be real careful not to nick the valve seat.

tiggermanoman

How much casting flash are there. All the heads I do I normally just deburr. When using die grinder with cutting bit, get some parifin wax (Gulf) like for canning. Run your die grinder sorta slow and let tool build up a coating of wax. Believe it or not the aluminum will not build up in the tool and it will actually sling the snot out of cutting what aluminum you want. When you do not see slivers flying, recoat with wax and go again. This saved my butt a many a time from old machinists. Once you have the ports done the way you want i use flapper wheel and finish out with rubber polishing wheel that is like a gigantic eraser. It gets the mirror finish that will flow and keep the carbon from building up. Like others said earlier. Just clean up the intake side and port match unless you take the valves out. If you really want them to flow you ought to pull valves and work on short side radius's and that will increase your flow. Hope this helps.