Polishing Pistons and Ports??

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Willgo
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Polishing Pistons and Ports??

Post by Willgo »

New to 2 storks this so might be dumb to sum.
On my GT380 the piston crowns and ports are rough, now on my 4stroks I would at lest smooth or polish them.
So is this not dun on 2stroks, I would have thought it would at least slowed down the carbon build up on the pistons and in exhaust pots?
Any enlightenment would be appreciated.
Regards Bill Dag.
Barry S.
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Re: Polishing Pistons and Ports??

Post by Barry S. »

I polished my GT750's head and exhaust ports to keep carbon buildup down, it helps.
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H2RICK
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Re: Polishing Pistons and Ports??

Post by H2RICK »

Absolutely, Bill, polish the pistons and exhaust ports. For sure you'll have less carbon buildup in those areas.
If you've got lots of time (and the desire), have a go at the transfers and intakes as well. Just don't be too "enthusiastic" with the Dremel. :wink: :D
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Coyote
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Re: Polishing Pistons and Ports??

Post by Coyote »

Polishing the intake ports is a great example of a bad idea. The fuel atomizes much better if those ports are left rough. Many a hot rodder spent mega hours polishing intake ports only to find out that it ran worse than it did before.
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tz375
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Re: Polishing Pistons and Ports??

Post by tz375 »

FYI, we never bother to polish anything on a race bike - apart from the paint and then only reluctantly. There is a tehoretical advantage to polishing piston crowns and ports to prevent carbon build up. But other tuners claim that a layer of carbon acts as an insulating layer to prevent heat transfer.

Polishing intakes and transfers is a bad idea under any and all scenarios though.

On race bikes we, seriously don't polish ports or pistons. Any theoretical advantage is not measurable in the real world, so I wouldn't bother.
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Re: Polishing Pistons and Ports??

Post by TLRam1 »

Coyote wrote:Polishing the intake ports is a great example of a bad idea. The fuel atomizes much better if those ports are left rough. Many a hot rodder spent mega hours polishing intake ports only to find out that it ran worse than it did before.

This what I have read also, otherwise your fuel lays like a sheet over the polished ports and may come off as such.
Terry

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Re: Polishing Pistons and Ports??

Post by H2RICK »

Well, you gents have a point with the better atomization thing. With the crap fuel we get these days, any improvement in atomization is bound to help combustion.
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Willgo
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Re: Polishing Pistons and Ports??

Post by Willgo »

MMMM
Looks like we full on the side of leave it as it is.
I guess by the time the charge has found its way up and down ports and flung round crankcases southing and blending is not going to do much.
I always smooth (Not polish) and blend the inlets on my 4stroks.
Doesn’t make a noticeable difference in power, but the engines do run smoother.
My thanks to you all :up:
Bill Dag.
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