How to Port & Polish Cylinder Heads

by Jesse James Dean
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Porting and polishing your cylinder heads will give your engine more horsepower and make it run more smoothly while increasing fuel efficiency. This process is done at many machine shops and can cost a good deal of money. If you are looking for a performance upgrade for your engine, porting and polishing your cylinder heads is the best way to get the most horsepower for your money, and you can do it yourself.

Step 1

Put the cylinder heads in a parts washer to soak for about 30 minutes to loosen any carbon buildup.

Step 2

Scrub the cylinder heads with a scrub brush and solvent.

Step 3

Blow the cylinder heads dry with compressed air and a blow gun.

Step 4

Set your intake manifold on the cylinder heads, matching all bolt holes. Spray the spray ink lightly into the intake ports of the manifold.

Step 5

Remove the manifold and locate the area that needs to be removed to make the ports match.

Step 6

Cut away with a die grinder and carbide-cutting bit until the ink mark is gone on all ports. This takes away any sharp edge that might slow the flow of air and fuel into the cylinder head.

Step 7

Put the exhaust manifold or header on each cylinder head with two bolts, one on each end, to hold it in place. Spray the ink up the hole of the exhaust manifold, adding compressed air at the same time to push the ink far enough up the manifold.

Step 8

Remove the exhaust manifold from the cylinder heads by removing the two bolts. You will be able to see what you have to grind away to make the cylinder head match the exhaust manifold or header.

Step 9

Grind the material away with the die grinder and carbide bit until the ink is gone.

Step 10

Smooth all ports with the die grinder and a polishing bit. Start with the intake port and remove all rough areas until it shines and is smooth. Repeat this process on the exhaust ports.

Step 11

Put your cylinder heads in the parts washer and scrub them vigorously. Let the solvent flow over them while scrubbing to wash away any metal filings.

Step 12

Blow-dry the cylinder heads with compressed air and a blow gun.

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