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Ok, sometimes I place too much of my self worth in how cheaply I can do things that otherwise would cost a lot. Hence the following question:
I have time, tools, and a cheap disposition: is it worth trying to port your own heads? If so, where can I get info on how to go about it?
(I have a garbage can full of degreaser, just so I don't have to pay to have my blocks cleaned.......I'm so ashamed:whacked: )
Sure,why not.A person can do a bowl blend,a little contour work around the valve guide area,a gasket match on both the intake and exhaust sides and polish the combustion chambers maybe even un-shroud the intake valve in the combustion area.Two things try and stay out of the valve seat area and never touch the short turn radius.
I understood, gasket match, polish combustion chamber, stay out of seat area,....., thats about it.
Bowl blend?
Contour around the valve guide??? what, relieve angles? clear out mass for better flow?
Unshroud intake valve in comb area? what clear area outside the
valve in the gasket plane? (obvious not going into gasket area)
Short run radius,,,not a clue
Pictures help me, but I'll take what I can get......:)
Go to E-bay item # 8004205960.Click on the picture of the small block Chevy head.This will give you some idea's.The short turn radius is the shorter side on the floor side.
Ok, I understand more now.
Do you use grinding stones or mill bits? (cast iron heads)
Those pictures are of a 4-pass CNC head and then finished by hand.You will need a good high speed di-grinder.Use an air powered unless you have arms like Arnold.I would start with a carbide bit.Don't go to a fast cut because they tend to jump around to much.When you get them all (roughed in) then go to your stones.Start with your roughest and then go to the finest and try to take all the cut marks out,then go to your taperd cartridge rolls roughest to finest,then go to your butterfly mandrels with sand paper strips going course to fine.On some of the aluminum heads I have done I might end up with 500 wet sandpaper in the combustion chambers.Be careful not to go smooth in the intake ports as far as grit try to stick around 120.Keep in mind you don't have a bracket car leaving against the brake.On the exhaust side I would try and go as smooth as the combustion chambers
Use old valves in the chambers to keep from scuffing the seats and don't surface the heads until you've done all the grinding. If you surface them first, sure as hell you'll run the burr up onto the shiny new surface :(