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HONDA
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Discussion Starter #1
high guys so after a lot of work i got all the carbon build up out the ports. removed most of the casting marks with a 120 grit mini sanding flap then by hand 180 grit water paper then 220 grit. im still thinking about 440 grit water paper too. but what you guy think?


im a little worried about tho's little pits.

should i be or is this a good polish? so ppl say 120 grid is a good polish.
 

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95 civic
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Good pics. Don't go to smooth or it can hurt performance. Smooth might flow better on a bench but on the strip it likes a little edge to it. 220 is where I'd stop
 

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1988 Honda CRX
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I go to 800 grit wet rubbed with WD40 on exhausts and chamber and chamber side of valves. I go 120 grit on outside rad and valve pocket of inlet and carbide bur finish on inside rad.

Smooth finish helps flow and decreases heat transfer and helps avoid carbon sticking.

Rough on inlet helps disperse fuel and rough inside rad helps column turn the corner by slowing the flow on the inside.
 

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1988 Honda CRX
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The pits look to deep to clean out without increasing the port size to much.
 

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HONDA
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Discussion Starter #5
I go to 800 grit wet rubbed with WD40 on exhausts and chamber and chamber side of valves. I go 120 grit on outside rad and valve pocket of inlet and carbide bur finish on inside rad.

Smooth finish helps flow and decreases heat transfer and helps avoid carbon sticking.

Rough on inlet helps disperse fuel and rough inside rad helps column turn the corner by slowing the flow on the inside.
so lost me... inside outside inside on....???? what???
 

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Discussion Starter #7
yeah i have been look in that post so are not as polished as this but some are insane bling. now i have been told by a few ppl to not go to bling for all sorts of reasons. even from ppl that have done bling before.

so i still have a long whey to go tho?
 

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1988 Honda CRX
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The ports are bent. They have to be so that the valve guide and spring have a place to go. The inside and outside is that bend. Inside rad is the bottom or short side. outside is the roof or long side.

To go around the corner, the air has to flow faster on the long side and slower on the short side. A rough surface slows the air down.

The reason for mirror finish is for thermal efficiency more than for volumetric efficiency. Smooth satin finish gives about as good as mirror finish re VE.

Bling has nothing to do with it.

You can win races without the mirror finish but the mirror finish makes real but hardly measurable improvments by keeping more heat in the chamber.
 

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Discussion Starter #9
so you say polish to 800 grit... ok wow... got a lot to do then.
 
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