port and polish.

[soryu]

so the kade will be brokendown this week.(need new seals)
and was thinking might as well get little extra work done and get it ported and polished.
just wanted to know around how much that costs?
or is this something that i could do on my own?(probably not):l101:

[Edwin562]

Local shop near me will charge around 500 for a fully ported and polished head.I need to double check though.

[nissanfreak317]

A proper port and polish will be done with a flowbench so that they can give you before and after readings and to equalize all the cylinders to flow similar amounts.
Your best bet is to find someone who is good at doing SR heads because they will know from past experience where they can take away material and where it doesn't help or is too close to a water jacket.

I worked at an automotive machine shop and on several occasions pressure tested heads that dudes had attempted to port and polish in their garage with a dremel and I found leaks where they had broken through into the water jacket without even realizing it. I wouldn't recommend doing it on your own unless you are just doing very simple cleaning up of the casting and polishing, no heavy port work.

[slydin240sx]

^ What he said....

[soryu]

where can i get some more info on doing a very simple cleaning up and polishing?

[nissanfreak317]

Take your head to whichever machine shop will be doing your valve job and resurfacing and allow them to disassemble it and clean it.
Tell them that you need to take the head for port work and take it home.
Buy a dremel and one of those extension things that lets you hold it like a pen.
Buy a set of those mini drum sander style things of varying diameters and some 220 grit sandpaper.
Remove rough areas in the casting but be extra careful of the gasket surfaces as well as the valve seats, screwing them up could be expensive.
Don't remove lots of material from anywhere, just look for anything that is an obvious casting flaw that obstructs air flow.
finish with the 220 grit to smooth it all out.
From what I understand, you really don't want to actually polish in there, a super smooth surface can be worse for your air flow than a lightly sanded one.

Just a quick FYI - sanding/smoothing will probably not show you much of a difference in power.

Either break down and spend the money to get your head properly ported and port matched/blueprinted and get some oversize valves in there, or don't do anything at all.

[rcdad123]

port flow is probably the closest shop to you that does a good job on porting heads. search for it to find reviews and results. also pricing, he did a full port and polish on my nephews acura gsr head for 900 bucks. thats including rebuilding the whole head.

[splitfire]

Just a quick FYI - sanding/smoothing will probably not show you much of a difference in power.

Either break down and spend the money to get your head properly ported and port matched/blueprinted and get some oversize valves in there, or don't do anything at all.

Thank you for advises. But nevertheless, I'm going to do a bit of porting work with my head and manifolds. Not just porting but rather smoothing, removing of imperfections and intake manifold port/gasket matching(leaving exhaust head-to-manifold steps along). I've never done porting work before, thus I have a couple of questions. Maybe any professional could give me some advice.

1. I want to remove these casting marks:
http://s018.radikal.ru/i503/1202/23/11aa8d774d86.jpg (http://radikal.ru/F/s018.radikal.ru/i503/1202/23/11aa8d774d86.jpg.html) http://s017.radikal.ru/i422/1202/43/4b14ce590a70.jpg (http://radikal.ru/F/s017.radikal.ru/i422/1202/43/4b14ce590a70.jpg.html)
I have a dremel, but it lacks of working bits, just drum sanders and couple of orange stones. I've tried them but they almost don't cut aluminum at all. What cutting bits should I buy? And what polishing bits for exhaust channels and combustion chamber?

2. I'm going to smooth sharp transition edges
http://s017.radikal.ru/i406/1202/9b/472fcee6dc3d.jpg (http://radikal.ru/F/s017.radikal.ru/i406/1202/9b/472fcee6dc3d.jpg.html)
but as you can see from another angle
http://s52.radikal.ru/i138/1202/9a/973690bf0948.jpg (http://radikal.ru/F/s52.radikal.ru/i138/1202/9a/973690bf0948.jpg.html)
valve seats are not flush with surface and form sharp edges themselves. Can I smooth these edges or I'll just ruin valve seats in this case?

3. And the last quick question: have I ruined the valves or a piece of fine grit emery paper could help:
http://s017.radikal.ru/i428/1202/8e/1db4fd21c5a4.jpg
?



P.S. Any help will be greatly appreciated, but please, don't advise me to find a reputable workshop with flowbench. I have no racing proven engine builders around. An ordinary workshop won't succeed in this work much better than me, cause they also will do it for the first time.

[splitfire]

Any advice?

[nissanfreak317]

Some of the stuff that you circled is just carbon deposits that can be easily cleaned.

You can use a regular carbide burr type thing to remove your circled areas, then use a sanding bit to smooth it out again. That shouldn't hurt anything.

Your valves are ok, the part that rusted is not the face that seals it, so just clean them with some emery paper, or whatever you'd like.

While you have everything apart, an easy trick to see if your valves are seating properly is this:
1. make sure not to mix up order of valves
2. use a black or blue Sharpie marker and coat the face of the valve that seats on the valve seat.
3. Insert valve into guide and "slap" it open and closed with your hand on either side repeatedly without rotating it.
4. you should see the marker removed wherever you have a good seal. All of your valves should develop a ring with no marker all the way around.

[splitfire]

Thank you.
Could you also answer my 2nd question, about valve seats on the 4th image. Is it possible to smooth edges of seats?

[redline racer510]

you can smooth your ports out with an aluminum flapper wheel if you dont want to spend money for a legit port and polish.

[nissanfreak317]

Thank you.
Could you also answer my 2nd question, about valve seats on the 4th image. Is it possible to smooth edges of seats?

I would advise you to not grind away any material from the actual valve seats. I missed that part of your post. Your valve seats are case hardened and very durable, but after you grind material away from them it will weaken them and the last thing you want is for one of them to come loose and fly around in there.

[splitfire]

Thanks a lot! You've been very helpful.

[Kingtal0n]

You may not notice any performance increase but its still a fun experience.

I would avoid any areas that involved moving parts- like valves.