How To Port And Polish?

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i want to give my b18a head a port and polish, was wondering if anyone knows any good sites, any good suggestions. thanks, matt

this is a major undertaking.. i was going to do it myself until i realized all the work that is involved... it is a difficult task and you can easily fuck a head up and make it flow worse

Here is a great site to try:

DIY Head porting

There is no reason, if you are comfortable pulling your cylinder head, that you can't have some fun learning how to port/polish. Of course an experienced shop will give you xx-hp in one shot, nice and reliable. But a simple clean-up is easy for anyone to do. :ph34r:

Couple of keys. Most P/P how-to's deal with 2-valve, iron heads. Reduce your tool speeds to about half of what you use for iron on aluminum and go slowly. Opt always for taking less than taking more. Remember, since you are new to this that Honda/Acura heads are good to begin with, you are just there to clean imperfections and eliminate hot spots. CLEAN thoroughly when you are done.

Best advice: Get another head to play with. B18a heads are reasonably and relatively cheap. If you mess up, you still have a car!

Good luck,

Dr. J.
Keep in mind this is only a mild PnP. I really just wanted to finally figure out how to post images, but here ya go.
You need 200-300 , Wet Sandable 800-1000 and 1500 Grit Sand Paper. Something to use to scrape some of the major build-up areas. Carbon-Cleaner (You dont really need it but it helps alot). Of course all the tools needed to get the Header off.

First port done. The one on the left is finished. The one on the right had a some of the first stage of sanding.

Started on the second port. Needs to be polished still but thats after the last stage of wet sanding.

Two more exhaust ports to go. This is turning out to be hard as with big hands your knuckles hit the exhaust manifold bolts/studs.

Pretty much done here , just a few things to touch up and on goes everything. I also sprayed some carbon cleaner in there.

Walla, put your header back on and enjoy.
dont even bother doing it like he says cause you're not gonna see any sort of gains. take it to a reputable machine shop that does pnp all day every day. i dont know where these people get this crap "walla, put your header back on and enjoy!" Yea, maybe enjoy the fact that you just :lol: wasted your time, and saw no results what so ever.
one word says it all: PORTFLOW
-let the experts handle shit like that on your car cuz they have "x" years experience and a good reputable shop can usually come through on a promise of "x" horsepower but you might do tons of work and only come out with like 0.75 know what I mean? I'm not saying you'll get so little power, I was just trying to prove a point.
If you want to give your own head a p&p, I say go for it. I did one on my dads car when we replaced the head gasket and valve seals and im in the process of doing my own. You might notice a bit of gain depending on your mods and its not that hard. The Standard Abrasives site is a good one to look at i found, just remember they are doing steel heads. In our case, aluminum is a bit harder to grind because of its tendancy to clog up the grindstone. Use grinders grease when your doing it and it should save you some trouble and possible injury. When hot aluminum gets into grindstone and heats up, the stone could shatter and thats bad especially when its spinning at a few thousand rpm.
Dude, I said "mild" if your expecting to get a second shaved off your quarter mile your a retard. No shyt going to a machine shop and handing over your pay check will get you a good port job, but mine only cost a dollar and 25 minutes.
Here's a great resource for information, pricing, etc...

PORT & POLISH BLOG This guy did the head on my '92 Civic Hatchback si. He writes a blog about it and can answer pretty much any question you have on it.
You guys fail to comprehend the point of an archived forum of information.

This guy contributed relevant data to a thread that will probably be found by people researching the topic, and all you do is spout off at the mouth with your "noob" drivel.

Thanks for posting, craigt. Don't mind the morons.
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