Cylinder port question

[rupedoggy]

Ben, I see that you read, research, and cruise the internet for a lot of the information that you share here. That can certainly be a good thing. Sometimes I think that an answer requires actual experience. I don't know how many saws that I have polished the exhaust, but it is a lot. How many have you done? I would state that all I have done have benefited with a noticeable increase in usable power. Don't discourage members from trying or wanting to try something. If you have not tried something yourself I don't feel that regurgitating materials you have gleaned elsewhere helps individuals asking questions. Mike


Been there, done that , got the t-shirt and am using it as a grease rag.

 

[bwalker]

Mike, I have had many two cycle motors built for me by some of the best two cycle guys in the country. Not one has a polished exhaust port.
To answer your question. I have not polished a one, because its a waste of time.

 

[Jwoods]

Lucky

The only way you're going to find out is to try it yourself. What's the worst that could happen?

 

[donho]

cylinder woes

Ok ive heard lots of do's and don'ts but didn't one guy ask about sharp edges in the ports for a stock saw it didn't sound like he was going to a race and besides this is my question too as I have a new jug and some of the the port edges to the cylinder bore are quite sharp should I sand them and with what grit ? and I didn once polish exhausts on a sbc I sure had more time then sure looked nice. :greenchainsaw:

 

[Lakeside53]

Ok ive heard lots of do's and don'ts but didn't one guy ask about sharp edges in the ports for a stock saw it didn't sound like he was going to a race and besides this is my question too as I have a new jug and some of the the port edges to the cylinder bore are quite sharp should I sand them and with what grit ? and I didn once polish exhausts on a sbc I sure had more time then sure looked nice. :greenchainsaw:

If it's a new jug, why are you worried about "sharp edge"? Surely the manufactures knows what they are doing? unless that is, you have a one of the less than stellar "aftermarket" jugs. Any "radius" you need around the ports is very small... so small you might even think it's "sharp".


I wouldn't use "sand paper" anyhow... A ball hone will do the job perfectly for you in a couple of stokes, but are you really sure you need anything done?

 

[slipknot]

Over at www.nwchainsaw.com he advertises porting and polishing the intake and exhaust ports, on a woods port service he offers. This guy is or was a arborsite sponser, I have never heard anything bad about him, and was considering contacting him about doing a woods port on a cub cadet cs5720,
which is the same as an efco 956, are guys saying this is a waste of $250?
Dern it I want a saw to brag to my friends about, one of those
"sleeper" saws as I would put it.

 

[TimberPig]

Over at www.nwchainsaw.com he advertises porting and polishing the intake and exhaust ports, on a woods port service he offers. This guy is or was a arborsite sponser, I have never heard anything bad about him, and was considering contacting him about doing a woods port on a cub cadet cs5720,
which is the same as an efco 956, are guys saying this is a waste of $250?
Dern it I want a saw to brag to my friends about, one of those
"sleeper" saws as I would put it.

Properly porting a saw will give a large power boost.

That wasn't the issue discussed in this thread however. The issue discussed was whether polishing the ports had any real benefit to the power output, and whther removing minor casting flaws would give any noticeable gains. Both will give negligible gains. The reason some like to polish the exhaust port is for reducing carbon buildup. Polishing the other ports will give no gains, and some theorize that polishing the intake and transfers actually reduces power, by affecting the turbulence of the airflow into the engine, thus inhibiting atomization and burning of the fuel/air charge.

If you want the port job, don't worry about the polishing part of it. The changes to the porting of the engine is what makes for power gains.