Is it common?

[moorhous]

Or ever done to just port a head and not polish it? A buddy of mine just bought a head off of ebay and it looks ported but not polished!

thanks

[maddmatt02]

ive heard of only the exhaust ports polished, and leaving the intake rough to help atomize the fuel

[moorhous]

Strang I cant see the if the exhaust ports are polished there black.

[GPracer2500]

The "polish" in "port and polish" doesn't necessarily mean finished to an extremely smooth or mirror finish. "Polishing" could mean finishing to a very smooth finish or it could mean finishing to a slightly course surface without burrs. There are some places in a head that you don't want to be as smooth as possible. Typically only the combustion chamber and the exhaust ports get smooth finishes. Some will debate the usefulness of doing that though. The intakes are typically left with a slightly rough finish. This helps produce a thin boundary layer of turbulence that keeps the fuel in the a/f mixture from coming out of suspension and pooling inside the ports.

In this context:
Port = change the shape
Polish = apply an appropriate surface finish

I prefer to just use the term "port" all by itself (e.g. "I had my ATV's head ported"). As far as I'm concerned, the term "porting" includes any surface finishing applied to various places within the head. I've always felt the term "port and polish" sounded a little hokey or old fashioned or something. JMO

$0.02

[drew416ex]

Originally posted by GPracer2500
The "polish" in "port and polish" doesn't necessarily mean finished to an extremely smooth or mirror finish. "Polishing" could mean finishing to a very smooth finish or it could mean finishing to a slightly course surface without burrs. There are some places in a head that you don't want to be as smooth as possible. Typically only the combustion chamber and the exhaust ports get smooth finishes. Some will debate the usefulness of doing that though. The intakes are typically left with a slightly rough finish. This helps produce a thin boundary layer of turbulence that keeps the fuel in the a/f mixture from coming out of suspension and pooling inside the ports.

In this context:
Port = change the shape
Polish = apply an appropriate surface finish

I prefer to just use the term "port" all by itself (e.g. "I had my ATV's head ported"). As far as I'm concerned, the term "porting" includes any surface finishing applied to various places within the head. I've always felt the term "port and polish" sounded a little hokey or old fashioned or something. JMO

$0.02

X2