Best way to polish inside ports/ round tubes

[xXSanderXx]

Maybe a noob question for the most guys here but what is the best way to polish and clean intake/exhaust manifold ports and round tubes/pipes?

Examples:

 

[Kevin54]

Look through Grainger, McMaster-Carr, MSCDirect, and some other tooling sites for buffing pads on long arbors. With some, you can mount them on an electrical motor, some you can put on a die grinder, or you can run them out of a hand drill. Your biggest thing is to get the polishing compounds that range from course to fine.

You may even have to make an extension for some of the buffing bobs. Do a search for Felt Bobs and you'll find what you are looking for.

 

[shoot summ]

Really depends on the condition of the port/pipe prior to polishing.

Back in the 2 stroke days I ported many cylinders, so I've done a bit of this on aluminum and steel.

Cartridge rolls on a mandrel help get you smoothed out.

https://www.google.com/search?q=car...e.1.69i57j0l3.4709j0&sourceid=chrome&ie=UTF-8

Once I had the surface smooth and uniform and had moved progressively finer on the cartridge rolls I would use a slotted mandrel and various finer grits of abrasive cloth, finally moving to strips of scotch brite, and then felt buffs and polishing compunds.

http://www.hardcorpabrasives.com/abrasive-products.php?id=152&cat=69

One thing I determined though is that high polish was really just for show on ports, fine scotchbrite and WD40 produced the same performance results.

 

[TwoInch]

keep in mind, that intake ports do not benefit from polishing like exhaust ports. leaving intake head and manifold ports in a "rough" condition is generally considered better by engine builders. it helps keep fuel atomized in the air flow, and helps promote fuel that is on the port wall to evaporate easier.

exhaust ports benefit from polishing because they are moving fry hot air, and getting it out is best case scenario. the mechanics of how intake and exhaust ports flow and work are totally different, and need to be considered when doing port work and matching.

 

[kald]

keep in mind, that intake ports do not benefit from polishing like exhaust ports. leaving intake head and manifold ports in a "rough" condition is generally considered better by engine builders. it helps keep fuel atomized in the air flow, and helps promote fuel that is on the port wall to evaporate easier.

exhaust ports benefit from polishing because they are moving fry hot air, and getting it out is best case scenario. the mechanics of how intake and exhaust ports flow and work are totally different, and need to be considered when doing port work and matching.

This^!!!!

 

[shawnspeed]

I have several 1/4" mandrels (slotted drill rod) made up for my die grinder that I simply just put crocus loth into....sorta just like a cheaper version of a flapper wheel that I can change grits on without having to use a wrench....and sheet stock is cheaper than pre made...Shawn

 

[xXSanderXx]

Thank you guys!

 

[tjsr19]

Do not polish intake or heads to a mirror finish you want them smooth but not that polished. If you do you can get condensation and hurt the motor. People don't always get that port and polish is an expression.