port and polish a 1y diesel?

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kingdalg
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port and polish a 1y diesel?

Post by kingdalg »

ok i know it sounds really chavvy and maxpower like...lol. but ive got a good 1y diesel engine ready for a mint recon job before i throw it in my devon. im very tempted to port and polish the head prior to the build up.... any thoughts? and no before people start carping on about flow charts and horsepower gained. i work on cars for a living and this build im doing for myself is the only that reminds how much i use to love working on motors compared to working on modern cr4p these days....... rant over.... haha a few days head work couldnt go amiss surely??? :ok

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Re: port and polish a 1y diesel?

Post by ghost123uk »

Polish v rough finish, rough finish causes turbulence that helps the fuel to become a vapour rather than liquid droplets, this makes it burn better ;)

The big WIKI says a lot especially when you get to this bit = The "Porting and Polishing" myth.

Though being a direct injection Diesel I suppose it makes even less difference ;)

Spend the time polishing the outside of it, the good look will make it feel faster :twisted:
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Re: port and polish a 1y diesel?

Post by footstuck »

I recon flow increase from polishing will help.
The distribution of fuel within the mixture is created by the positioning of the flame mouth and internal squelch of the Ricardo Comet combustion chamber within the cylinder head.
As the piston rises the compressing air is forced into the combustion chamber through the flame mouth which is positioned off-center to the spherical combustion chamber. This causes the compressing air to spin as the air charge enters the RC
Diesel injection then commences and the design allows excellent fuel/air distribution.
After the bang the rapidly expanding gasses then exit the chamber through the flame mouth directly onto the crown of the piston.
Polish the inside More than out in my opinion :ok
Found this.
http://www.google.co.uk/url?sa=i&source ... 6385931686" onclick="window.open(this.href);return false;

max and caddy
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Re: port and polish a 1y diesel?

Post by max and caddy »

I always port any engine I intend to use and always seem to have an edge over others that haven't been...polish is pointless but smoothing out the lumps and matching up gasket faces is good.

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Re: port and polish a 1y diesel?

Post by Plasticman »

As ^^^^^, matching head to manifolds and easing sharp angles and getting rid of rough spots is always worjth while,
mm

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