DIY: Head porting for dummies

[AceInHole]

As some of you know... I'm attempting to port and polish my head since I've got nothing else to do with it without a head gasket....

Here's the exhaust side:


Believe it or not this is AFTER a bit of cleaning. There were literally CHUNKS of carbon deposits stuck to the floor and divider of the port. I had to use a screwdriver to chunk them off since WD-40 and paper towels weren't working at all. Just cleaning out the carbin deposits would probably help regain lost power a LOT.


A stainless steel brush on a dremel helps clean the port out. I did everything with the valves in, which probably isn't the best idea, but it makes things easier since taking all the valves out is a PITA. I obviously couldn't get as deep into the port as I wanted to, but I was able to do a lot anyways.


This is after the course abrasive buff: 180-220 grit. Helped to clean out the port even more and gave it a nice finish. At this point I really should have taken out the castings, but at the time I didn't feel like switching wheels. I'll most likely get to it tomorrow and do it before the final round of buffing.


This is after the medium abrasive buff: 280-320 grit. Notice how you can see the reflection of the divider on the floor of the port. It's getting there....

Well, I wasn't able to get the fine abrasive buff since Sears wasn't open. I was limited to the selection at a Super Walmart (open 24 hours) since I got out of work at 9pm.

So far, here's the stock intake port to what I've done so far:

All I really did was take out the extra casting and widen out a "lip" part to the port entrance.

I'll post more on the intake side later after finishing up the exhaust side (which really is more important on a turbo car I think....)

I'm following this as a guide, a really good informative page:
http://www.sa-motorsports.com/diyport.htm

[240racer]

thank goodness for wal-mart. You are correct when you say the exhaust is more important for turbo aps. I have my head off and maybe I'll do some work on it now that you have paved the way for your fellow zilvians.

[AceInHole]

Took the head off?? Get a headgasket for it already?? It took like 2 weeks just to get the thing shipped out.... and then you have to wait for the shipping company to make good on their 2-day air.
After this ordeal I'm gonna buy an extra headgasket just to have handy... that and I plan on doing more headwork on a spare head after I'm up and running.

[240racer]

where did you get a headgasket from? I figured that it wouldn't be that hard to buy, oops. I also have to get a rebuild kit with seals and bearings, and I thought the head gasket was included in that.
thanks

[Kreator]

Originally posted by 240racer
where did you get a headgasket from? I figured that it wouldn't be that hard to buy, oops. I also have to get a rebuild kit with seals and bearings, and I thought the head gasket was included in that.
thanks

http://www.partsamerica.com/

Pt#: 035-1940

but nomatter whom you buy it from, look for something in that price range. Reason for that i saw a site that was selling the same gasket for $130 (prolly a typo), but none the less, i almost ordered it

[transient]

A head gasket should be included in a top end rebuild kit.

[AceInHole]

Well, he'll probably want to stick with an OEM gasket since it's been proven as the strongest so far. All the KA turbo guys are usin' em

I ordered mine from http://www.nismoparts.com
Part #........... Description........ List.... Unit Price
11044-53F00 Gasket-cylinder $40.37 $30.76

Although, it took like two weeks for it to even ship out (I'm picking mine up tomorrow, YAAY!), you can't find a better price (I couldn't) on an OEM head gasket. It could be worse, boosteds14 said he waited like a month for his first OEM headgasket from Courtesy Nissan.

[Bolo]

I just recently ported the exhaust side on my sr. But I didn't port each individual runner, only where the manifold meets the turbo and where the turbo meets the elbow. I ported the openings to match the gaskets and just tried to smooth out everything in there.

Now the turbo spools up much quicker with almost no lag! And there is a very noticable difference in drivability as the power comes on a lot sooner at lower rpm's. I highly recommend porting, especially on turbo cars!

[AceInHole]

Originally posted by Bolo
I just recently ported the exhaust side on my sr. But I didn't port each individual runner, only where the manifold meets the turbo and where the turbo meets the elbow. I ported the openings to match the gaskets and just tried to smooth out everything in there.

Now the turbo spools up much quicker with almost no lag! And there is a very noticable difference in drivability as the power comes on a lot sooner at lower rpm's. I highly recommend porting, especially on turbo cars!

Port matching on the exhaust side is supposedly not as good.... the site I listed in my first post warns against it unless it's absolutely necessary.

Quote from that site:

In most cases, you never port match the exhausts. Many stock exhaust manifolds and virtually all tube headers will have larger port sizes than do the heads. You want that "step" from the port to the larger header tube or exhaust manifold because, as pressure pulses flow back and forth in the exhaust system, it acts as a "reversion dam" by resisting back flow of exhaust gases into the port. If you end up with the rare situation where the stock exhaust manifold has ports smaller than those in the head, you will need to port match.

[Bolo]

Well I didn't port the manifold where it meets the head cuz I saw that the manifold port was larger than the head port. So I figured I should just leave it alone. I just tried to make the exhaust flow through the turbo as smooth as possible.

[AceInHole]

Originally posted by Bolo
Well I didn't port the manifold where it meets the head cuz I saw that the manifold port was larger than the head port. So I figured I should just leave it alone. I just tried to make the exhaust flow through the turbo as smooth as possible.

Well, the thing about exhaust gas is that it pulses (much like air in the intake plenum and runners). Supposedly the mismatch in size helps decrease the back pulses, at least from what that site says. I noticed on my manifold that the ports are MUCH smaller than the gaskets, so I'm porting the manifold to the gaskets and leaving the head pretty much alone. Guess I'll see how it goes when it's all up and running. So many variables though with the 248 intake cam and ported intake..... it'll be hard to tell where any gains/ losses are coming from, but if it's a big gain, then it's most likely the whole package i guess.

[d240t2]

FYI, Courtesy Nissan quoted me $35.46 for the OEM KA headgasket. That is a discounted 240SX CCA member (I have ordered from them about 7 times in the past 3 yrs), not a discounted shop price. That beats out the price you got, AceInHole.

And next time...don't try and use WD40 to clean up stuff like that. Use carb cleaner. WD40 is good for cleaning up hoses and stuff...but carb cleaner is what you need to use to clean up crud and exhaust carbon buildup like that.

We buy it by the case at UH.

Dennis

[AceInHole]

Originally posted by d240t2
FYI, Courtesy Nissan quoted me $35.46 for the OEM KA headgasket. That is a discounted 240SX CCA member (I have ordered from them about 7 times in the past 3 yrs), not a discounted shop price. That beats out the price you got, AceInHole.

How is $35.46 less than $30.76?? I think you were looking at the list price.

[/b]And next time...don't try and use WD40 to clean up stuff like that. Use carb cleaner. WD40 is good for cleaning up hoses and stuff...but carb cleaner is what you need to use to clean up crud and exhaust carbon buildup like that. [/B]

Yeah, WD40 was just what I had sitting on the table at my apt. When I brought it home I cleaned it out with brake cleaner (quick drying). For the gunked stuff tho, the steel brush worked like a charm.

[sL103]

actually you dont want it that smooth though. at the most you should have went about rough , med then an 80 flap wheel which will actually give you a pretty nice swirl effect if done right. if you didnt use gaskets your pretty much set as long as you didnt hog it out. hope you didnt take too much of the port floor you can almost leave the port floor alone. you can further take this process alot more if you want.

port match the intake manifold to the head. and port out your exhaust manifold. no port matching to the head. but not too bad though. ill be porting a buddies 300ZX twinturbo upper and lower plenums together so i can post some pics or you can check out my home page http://sl103.tripod.com

Shawn

[AceInHole]

Well, I pretty much left the ports alone. The only things I really did were to take the extra casting off of the sides of the ports, and polish the exhaust ports (which you want as smooth as possible). I also ported out the exhaust manifold to the gasket, and it's all just about done for now.

[AceInHole]

head is ported and installed!!

Impressions:
I'm pretty sure most of it is the manifold porting, but overall the engine DEFINITELY breathes easier. The turbo starts spooling virtually as soon as I hit the throttle, and I'm at full boost MUCH earlier than before!! I didn't install the 248deg exhaust cam yet though.... but I'd imagine that it'd just add to the great response the engine has now. Aside from the sounds (whistling and BOV) the car as such a linear and instant powerband that it still has a somewhat NA feel to it. But... this could all just be that I've been driving a minivan lately...... I'll get some vids up and show you peeps what it's like tho.

[kandyflip445]

Post the vids!!! Congrats on your successful head.....porting...

[d240t2]

Originally posted by AceInHole

How is $35.46 less than $30.76?? I think you were looking at the list price.[/B]

Cheaper than the Beck Arnley gasket from parts america that someone else posted...that is what I meant.

[AceInHole]

Originally posted by d240t2
Cheaper than the Beck Arnley gasket from parts america that someone else posted...that is what I meant.

oh, yeah.

how was the availability of the gasket though? boosteds14 said it took like a month to get his from courtesy.... took like 3 weeks to get mine from nismoparts.com.

[d240t2]

I didn't ask about the availability...but usually, it only takes a week for me to get something from them.

It all depends. You really only have 2 data points for comparison between you and Boosted...so you can't really draw conclusions from that (ie, nismoparts is faster than courtesy).

Dennis

[mrdirty]

Ace: honestly I don't know $hit about porting but congratulations; that's awesome that u even tried.....I miss my garage.

[AceInHole]

Originally posted by d240t2
I didn't ask about the availability...but usually, it only takes a week for me to get something from them.

It all depends. You really only have 2 data points for comparison between you and Boosted...so you can't really draw conclusions from that (ie, nismoparts is faster than courtesy).

Dennis

Yeah... I'm not trying to say they're faster or not though... it'd just help a lot to know how long it might take to get your part, which is why I asked how long it takes you to get them (guess i should've worded it better? by availability, that's pretty much what i meant).

[92s13]

I might have to try this...

[AceInHole]

Originally posted by 92s13
I might have to try this...

Yeah. Used heads are fairly cheap. There's another one near me I might buy for $80. Got mine from a junkyard with a 1yr. warranty for $100. So.... if you mess it up it isn't TOO big of a loss. Swapping heads is a PITA though.

[adammmmmm]

Not to get off topic but, I'm looking for more information about getting the head & new gaskets back ON the block, i'm doing this in my recently acquired coupe and i've never done this on a car with chains, i've searched for a few weeks now, please help!(I'd rather not post a new thread)


good info on the porting btw.

[Mikey88]

2003 thread bro ...get a fsm and work from there if you dont have one..

[idahotuner]

i wihs the pictures were still linked i would be interested to read it.

[adammmmmm]

It never hurts to bump an old thread and ask for help?..


sorry dudes.

[Jonnybonds]

I've been looking into port and polishing my head myself, I would like to see some pics as an example to go by. Anyone got pics of their heads after a port and polishing..................POST THEM UP!!!!!.