Heres another thread discussion i read
Did you polish the intake side?
-No ive just honed it, your not ment to polish it past were the injectors shoot into the head as the rough surface is meant to incourage turbulance which inturn mixes the fuel with air.....so im told.
Did you port match the intake and exhaust manifolds, and knife edge the ports there is a whole list of shit you can do.. but make everything matched and you should see some decent gains.
-Ive been reading the book on engine blueprinting and alsoo cylinder head porting principles so inspired me to do my own..its not really ported out i was just looking to improve the efficiency of the ports not sure wether ive said it already but it was saying that turbo cars respond better to smaller faster velocity ports so i didnt want to remove too much material. Heres what ive done so far..ive picked up another head too which im going to measure the caspacity of the ports and use latex to check port shape..will do a write up soon
step one: basic degrease of the head..valves removed, cleaned using 'gunk'
step two: hard to remove deposits were removed with a dremel and a pannel flap..also 80 gritt paper proved pretty useful on the end of the finger.
step three: once the majority of the crap was removed from the exhaust ports i just started honing them out with the pannel flap wheel..moving in and out radiusing the port..removing obsticles in the way. The ridge between the port opening and the valve has been smoothed-turning a kink into a smooth semi circle to improve gas flow. its suprising how much material i did remove judging by wat was left on the desk..lol
step four: well the dremel with the sanding wheel gave a good enough finish but for the exhaust ports to prevent carbon build up i thought it was a good idea to mirror polish the runners..excessive i know but because im learning i though why not as i was beginning to feel more confident with the tool. from 250-400-800-1000-1500 i rubbed the ports smooth by hand..took a month of saturdays lol..you know when they good as they become super smooth and a dull satin shine.
step five: autosol!! wicked polishing product..loaded up on a polishing wheel on the dremel mirrors the ports quickly and then buffed by hand.
Warning; i used masking tape wrapped tightly around the chuck of the rotary tool to prevent damaging the valve seats when cleaning the bowls..pannel flap wheel was ideal for this again, slowly massaging the runners with the tool with a steady pressure.
I wasnt to bothered about removing loads of material and didnt want to go into the water channels so by following the runners shape has stayed uniform
once ive chosen my manis il do a better write up with port matching and also replacing the valve stem seals.
Im confused im also in the process of pnp my d15b2 head and still debating on what is better if i should match the intake manifold side and port and polish it but have also read not to polish the intake side
so whats best?
Dont polish the intake manifold side the goal is to have mirror smooth exhaust ports a polished combustion chamber and just a ported intake ports like he said it helps keep the fuel mixed with the air.
Hope all this helps you out!